Computer system interface surface

• US 6,832,717 B1
• Filed: 05/23/2000
• Issued: 12/21/2004
• Est. Priority Date: 05/25/1999
• Status: Expired due to Fees

• Current Assignee: Silverbrook Research Pty Limited
• Original Assignee: Silverbrook Research Pty Limited
• Inventors: Lapstun, Paul, Silverbrook, Kia
• Primary Examiner(s): Lee, Michael G.
• Assistant Examiner(s): Lee, Seung H
• Application Number:
  US09/575,188
• Time in Patent Office: 1,673 Days
• Field of Search: 235/380, 235/376, 235/462.45, 235/462.46, 235/454
• US Class Current: 235/380
• CPC Class Codes: B41J 13/103 for the sheet feeding section
• CPC Class Codes: B41J 13/106 for the sheet output section
• CPC Class Codes: B41J 2/17503 Ink cartridges
• CPC Class Codes: B41J 2/17513 Inner structure
• CPC Class Codes: B41J 2/1752 Mounting within the printer
• CPC Class Codes: B41J 2/17523 Ink connection
• CPC Class Codes: B41J 2/17546 electronically
• CPC Class Codes: B41J 2/17553 Outer structure
• CPC Class Codes: B41J 2/17556 Means for regulating the pressure in the cartridge
• CPC Class Codes: B41J 2/17563 Ink filters
• CPC Class Codes: B41J 2/2114 Ejecting specialized liquids, e.g. transparent or processing liquids B41J2/211 takes precedence
• CPC Class Codes: B42C 19/02 starting with single sheets
• CPC Class Codes: B42C 9/0006 by applying adhesive to a stack of sheets
• CPC Class Codes: B42C 9/0081 applying adhesive to individual sheets for binding them together by fusing, welding B42C9/0093
• CPC Class Codes: B42P 2261/04 Producing books by printing sheets in following order, e.g. for ordering via the Internet
• CPC Class Codes: B65H 29/34 from supports slid from under the articles
• CPC Class Codes: B65H 37/04 for securing together articles or webs, e.g. by adhesive, stitching or stapling adhering replacement to expiring web during change of web roll B65H19/18
• CPC Class Codes: G06F 16/00 Information retrieval; Database structures therefor; File system structures therefor
• CPC Class Codes: G06F 3/016 Input arrangements with force or tactile feedback as computer generated output to the user
• CPC Class Codes: G06F 3/0321 by optically sensing the absolute position with respect to a regularly patterned surface forming a passive digitiser, e.g. pen optically detecting position indicative tags printed on a paper sheet constructional details of pen-shaped pointing devices G06F3/03545, G06F3/03542, G06F3/037
• CPC Class Codes: G06F 3/03545 : Pens or stylus
• CPC Class Codes: G06F 3/04883 : for inputting data by handwriting, e.g. gesture or text
• CPC Class Codes: G06F 3/1204 : resulting in reduced user or operator actions, e.g. presetting, automatic actions, using hardware token storing data
• CPC Class Codes: G06F 3/1265 : Printing by reference, e.g. retrieving document/image data for a job from a source mentioned in the job
• CPC Class Codes: G06F 3/1284 : Local printer device
• CPC Class Codes: G06K 17/00 : Methods or arrangements for effecting co-operative working between equipments covered by two or more of main groups G06K1/00 - G06K15/00, e.g. automatic card files incorporating conveying and reading operations
• CPC Class Codes: G06Q 20/346 : Cards serving only as information carrier of service
• CPC Class Codes: G06Q 20/40 : Authorisation, e.g. identification of payer or payee, verification of customer or shop credentials; Review and approval of payers, e.g. check credit lines or negative lists
• CPC Class Codes: G06Q 30/00 : Commerce
• CPC Class Codes: G06V 30/10 : Character recognition
• CPC Class Codes: G06V 30/1423 : the instrument generating sequences of position coordinates corresponding to handwriting preprocessing or recognising digital ink G06V30/32
• CPC Class Codes: G06V 30/1426 : by sensing position defining codes on a support
• CPC Class Codes: G06V 30/1448 : based on markings or identifiers characterising the document or the area
• CPC Class Codes: G07F 7/1008 : Active credit-cards provided with means to personalise their use, e.g. with PIN-introduction/comparison system
• CPC Class Codes: H04N 1/00127 : Connection or combination of a still picture apparatus with another apparatus, e.g. for storage, processing or transmission of still picture signals or of information associated with a still picture
• CPC Class Codes: H04N 1/00204 : with a digital computer or a digital computer system, e.g. an internet server programmed control between transmitter and receiver or between image input and image output device H04N1/32561
• CPC Class Codes: H04N 1/00244 : with a server, e.g. an internet server fax-servers or the like for store and forward H04N1/324
• CPC Class Codes: H04N 1/00326 : with a data reading, recognizing or recording apparatus, e.g. with a bar-code apparatus arrangements for the associated working of recording or reproducing apparatus with related apparatus G11B31/00
• CPC Class Codes: H04N 1/00358 : Type of the scanned marks
• CPC Class Codes: H04N 1/00376 : Means for identifying a mark sheet or area
• CPC Class Codes: H04N 1/00567 : Handling of original or reproduction media, e.g. cutting, separating, stacking
• CPC Class Codes: H04N 1/00968 : by scanning marks on a sheet mark-sheet input means H04N1/00355; sensing record carriers G06K7/00
• CPC Class Codes: H04N 1/32101 : Display, printing, storage or transmission of additional information, e.g. ID code, date and time or title
• CPC Class Codes: H04N 1/32122 : in a separate device, e.g. in a memory or on a display separate from image data
• CPC Class Codes: H04N 1/32128 : attached to the image data, e.g. file header, transmitted message header, information on the same page or in the same computer file as the image for information embedded in the image H04N1/32144
• CPC Class Codes: H04N 1/32771 : in response to a request, e.g. for a particular document
• CPC Class Codes: H04N 1/32778 : using a mark-sheet or machine-readable code request
• CPC Class Codes: H04N 2201/0082 : Image hardcopy reproducer H04N2201/0091 - H04N2201/0094 take precedence
• CPC Class Codes: H04N 2201/3243 : of type information, e.g. handwritten or text document
• CPC Class Codes: H04N 2201/3247 : Data linking a set of images to one another, e.g. sequence, burst or continuous capture mode
• CPC Class Codes: H04N 2201/3249 : data relating to a linked page or object, e.g. hyperlink
• CPC Class Codes: H04N 2201/3269 : of machine readable codes or marks, e.g. bar codes or glyphs
• CPC Class Codes: H04N 2201/327 : which are undetectable to the naked eye, e.g. embedded codes

Abstract

A method and system for enabling user interaction with computer software running in a computer system. The user interaction is via an interface, such as a sheet of paper bearing information relating to the computer software and coded data indicative of an interactive element relating to the computer software. A sensing device is placed in an operative position relative to the interface surface, and senses indicating data indicative of the interactive element. The sensing device also generates movement data indicative of the sensing device'"'"'s movement relative to the interface surface. The indicating and movement data from the sensing device are received in a computer, and the interactive element identified. The computer software is then operated at least partly in reliance on the movement data, and in accordance with instructions associated with the interactive element.

Claims

1. A method of enabling user interaction with computer software running in a computer system, the method including the steps of:

(a) providing an interface surface containing;

human-readable information relating to the computer software; and

coded data indicative of at least one interactive element relating to the computer software, wherein the information and the coded data are printed substantially simultaneously onto a substrate; and

in the computer system;

(b) receiving indicating data from a sensing device, the indicating data being generated using coded data sensed in response to placing of the sensing device in an operative position relative to the interface surface and being indicative of;

(i) the at least one interactive element; and

(ii) movement of the sensing device relative to the interface surface,

(c) determining movement of the sensing device to the interface surface from the indicating data;

(d) identifying the at least one interactive element from the indicating data; and

(e) operating the computer software at least partly in reliance on the movement data, and in accordance with instructions associated with the at least one interactive element.

2. A method according to claim 1, wherein the interactive element is a hyperlink element relating to the computer software, the method including the step of effecting, in the computer system, an operation associated with the hyperlink element.

3. A method according to claim 2, including the step of sending, in the computer system, data to the computer software indicative of the hyperlink element.

4. A method according to claim 3, including the step of sending, in the computer system, data to the computer software indicative of a name and/or value of at least one field related to the computer software.

5. A method according to claim 2, including the step of sending, in the computer system, data to the computer software indicative of a selected object.

6. A method according to claim 1, wherein the interactive element is a checkbox field relating to the computer software, the method including the steps of identifying, in the computer system, that the user has entered a hand-drawn mark by means of the sensing device and effecting, in the computer system, an operation associated with the checkbox field.

7. A method according to claim 6, including the step of associating, in the computer system, a true value with the checkbox field.

8. A method according to claim 6, including the step of sending, in the computer system, data to the computer software indicative of at least the checkbox field.

9. A method according to claim 1, wherein the interactive element is a text field relating to the computer software, the method including the steps of identifying, in the computer system, that the user has entered handwritten text data by means of the sensing device and effecting, in the computer system, an operation associated with the text field.

10. A method according to claim 9, including the step of converting, in the computer system, the handwritten text data to computer text.

11. A method according to claim 10, including the step of associating, in the computer system, the computer text with the text field.

12. A method according to claim 9, including the step of sending, in the computer system, data to the computer software indicative of at least the text field.

13. A method according to claim 1, wherein the interactive element is a signature field relating to the computer software, the method including the steps of identifying, in the computer system, that the user has entered a handwritten signature by means of the sensing device and effecting, in the computer system, an operation associated with the signature field.

14. A method according to claim 13, including the step of verifying, in the computer system, that the signature is that of the user.

15. A method according to claim 14, including the step of generating, in the computer system and using a signature key of the user, a digital signature of at least data indicative of a name and/or value of at last one field related to the computer software.

16. A method according to claim 15, including the step of associating, in the computer system, the digital signature with the signature field.

17. A method according to claim 13, including the step of sending, in the computer system, data to the computer software indicative of at least the signature field.

18. A method according to claim 1, wherein the interactive element is a drawing field related to the computer software, the method including the steps of identifying, in the computer system, that the user has entered a hand-drawn picture by means of the sensing device and effecting, in the computer system, an operation associated with the drawing field.

19. A method according to claim 18, including the step of activating, in the computer system, a hyperlink.

20. A method according to claim 18, including the step of sending, in the computer system, data to the computer software indicative of at least the drawing field.

21. A method according to claim 1, wherein the step of printing the interface surface onto the substrate is performed on demand.

22. A method according to claim 1, wherein the coded data is printed onto the surface to be substantially invisible to an unaided human eye.

23. A method according to claim 1, including the step of retaining a retrievable record of each interface surface printed, the interface surface being retrievable using the identity contained in its associated coded data.

24. A method according to claim 1, including the step of distributing a plurality of the interface surfaces using a mixture of multicast and pointcast communications protocols.

25. A method according to claim 1, the sensing device containing an identification means that imparts a unique identity to the sensing device and identifies it as belonging to a particular user, wherein the method includes the step of monitoring, in the computer system, said identity.

26. A method according to claim 1, including the step of providing sufficient information relating to the computer software in the interface surface to eliminate the need for a separate display device.

27. A method according to claim 1, wherein the interface surface is printed on multiple pages, the method including the step of binding the pages.

28. A method according to claim 1, wherein the coded data includes at least one tag, each tag being indicative of the at least one interactive element.

29. A method according to claim 28, wherein each of the tags includes identity data defining the at least one interactive element.

30. A method according to claim 28, wherein the surface is defined by a substrate.

31. A method according to claim 30, wherein the substrate is laminar.

32. A method according to claim 28, wherein the tags are disposed at predetermined positions on the surface.

33. A method according to claim 32, wherein the tags are disposed on the surface within a tessellated pattern comprising a plurality of tiles, each of the tiles containing a plurality of the tags.

34. A method according to claim 33, wherein the tiles interlock with each other to substantially cover the surface.

35. A method according to claim 34, wherein the tiles are all of a similar shape.

36. A method according to claim 35, wherein the tiles are triangular, square, rectangular or hexagonal.

37. A method according to claim 33, wherein the tags are disposed stochastically within each of the tiles.

38. A method according to claim 28, wherein each of the tags includes at least one common feature in addition to the identity data.

39. A method according to claim 38, wherein one or more common features are configured to assist finding and/or recognition of the tags by associated tag reading apparatus.

40. A system according to claim 39, including the step of activating, in the computer system, a hyperlink.

41. A method according to claim 38, wherein the one or more common features are represented in a format incorporating redundancy of information.

42. A method according to claim 41, wherein the at least one common feature is rotationally symmetric so as to be rotationally invariant.

43. A method according to claim 41, wherein the at least one common feature is ring-shaped.

44. A method according to claim 28, wherein each of the tags includes at least one orientation feature for enabling a rotational orientation of the tag being read to be ascertained.

45. A method according to claim 44, wherein the at least one orientation feature is represented in a format incorporating redundancy of information.

46. A method according to claim 45, wherein the at least one orientation feature is rotationally asymmetric.

47. A method according to claim 45, wherein the at least one orientation feature is skewed along its major axis.

48. A method according to claim 28, wherein each of the tags includes at least one perspective feature for enabling a perspective distortion of the tag being read to be ascertained.

49. A method according to claim 48, wherein the at least one perspective feature includes at least four sub-features which are not coincident.

50. A method according to claim 28, wherein each tag includes a plurality of tag elements, the identity data each being defined by a plurality of the elements.

51. A method according to claim 50, wherein the tag elements are disposed in one or more arcuate bands around a central region of each tag.

52. A method according to claim 51, wherein there are a plurality of the arcuate bands disposed concentrically with respect to each other.

53. A method according to claim 52, wherein each element takes the form of a dot having a plurality of possible values.

54. A method according to claim 53, wherein the number of possible values is two.

55. A method according to claim 53, wherein when representing one of the possible values, the tag elements absorb, reflect or fluoresce electromagnetic radiation of a predetermined wavelength or range of wavelengths to a predetermined greater or lesser extent than the surface.

56. A method according to claim 53, wherein the possible values of the tag elements are defined by different relative absorption, reflection or fluorescence of electromagnetic radiation of a predetermined wavelength or range of wavelengths.

57. A method according to claim 53, wherein the tags are not substantially visible to an average unaided human eye under daylight or ambient lighting conditions.

58. A method according to claim 53, wherein the tags are slightly visible to an average unaided human eye under daylight or ambient lighting conditions.

59. A method according to claim 53, wherein the tags are visible to an average unaided human eye under daylight or ambient lighting conditions.

60. A method according to claim 28, wherein the identity data is represented in a format incorporating redundancy of information.

61. A method according to claim 28, wherein the tags are printed onto the surface by means of a printer.

62. A method according to claim 61, wherein the printer is an ink printer.

63. A method according to claim 62, wherein the tags are printed using ink that is absorbent or reflective in the ultraviolet spectrum or the infrared spectrum.

64. A method according to claim 61, wherein the printer also prints additional information onto the surface.

65. A method according to claim 64, wherein the additional information is printed onto the surface using colored or monochrome inks.

66. A method according to claim 65, wherein the additional information is printed onto the surface using one of the following combinations of colored inks:

CMY;

CMYK;

CMYRGB; and

spot colour.

67. A method according to claim 28, wherein at least a plurality of the tags are disposed stochastically upon the surface.

68. A method according to claim 28, wherein the tags are disposed in a regular array on the surface.

69. A method according to claim 68, wherein the array is triangular.

70. A method according to claim 68, wherein the array is rectangular.

71. A method according to claim 68, wherein the tags are tiled over the surface.

72. A method according to claim 28, further including additional non-tag information disposed on the surface.

73. A method according to claim 1, wherein the region is identified with sufficient precision to distinguish the region from 1.5×

10¹⁴ other regions.

74. A method according to claim 1, wherein any 10 millimeter diameter subregion of the region includes sufficient information to identify the region.

75. A method according to claim 74, wherein any 10 millimeter subregion of the region includes sufficient information to identify at least one point of the region.

76. A method according to claim 1, wherein the sensing device includes at least one acceleration measuring device for measuring acceleration of the sensing device as it is used to draw the user input onto the surface, the movement data being generated by periodically sampling the acceleration of the sensing device as it is used to draw the user input onto the surface.

77. A method according to claim 76, further including the step of generating movement data in the form of a locus of the sensing means in relation to the surface, the locus being determined by ascertaining relative displacement of the sensing means due to its velocity within each sampling period.

78. A method according to claim 77, wherein the accelerometers are configured to measure at least two orthogonal components of acceleration.

79. A method according to claim 1, including the step of providing the user with printed information including position elements, the position elements being disposed on a surface, the sensing device being configured to periodically sense position elements as it is used to draw the user input onto the surface, the method including the step of generating the movement data in the form of a locus of the sensing means in relation to the surface by ascertaining relative displacement of the sensing means with respect to at least one of the position elements.

80. A method according to claim 79, wherein the position elements are disposed on the surface as a regular array of dots, lines or other formations.

81. A method according to claim 79, wherein the position elements are disposed on the surface stochastically.

82. A method according to claim 1, wherein the movement data is generated by ascertaining a locus of the sensing device in relation to the surface by ascertaining relative movement of one or more motion sensing elements rotatably mounted to the sensing device for contact with the surface while the sensing device is used to draw the user input thereon.

83. A method according to claim 82, wherein the motion sensing elements include one or more rollerballs mounted for rotation within a constraining housing disposed substantially within the sensing device.

84. A method according to claim 83, wherein components of rotation of the rollerball, due to movement of the sensing device when drawing the user input onto the surface, are periodically measured.

85. A method according to claim 84, wherein the components of rotation of the rollerball due to movement of the sensing device by the user when drawing the user input onto the surface are measured by means of:

rollers disposed within the constraining housing for rotation, the rollers being configured to be driven by contact with the rotating rollerball;

or

optical sensing of rotation of the rollerball with respect to the constraining housing.

86. A method according to claim 1, wherein the movement includes at least one stroke.

87. A method according to claim 85, wherein a stroke is initialised when the pen is placed in an operative position relative to the interface surface and is completed when the pen is removed from the operative position.

88. A method according to claim 1, wherein the indicating data is indicative of a sequence of pen positions, the pen positions being determined by sensing of the coded data.

89. A method according to claim 88, wherein the indicating data is further indicative of the relative time at which each pen position is determined.

90. A method according to claim 1, wherein the indicating data is indicative of a number of strokes, each stroke being represented by a respective sequence of pen positions.

91. A method according to claim 90, wherein each stroke is further represented by an identifier indicative of an identity of the interface surface.

92. A method according to claim 90, the number of strokes representing handwritten text.

93. A system for enabling user interaction with computer software via:

an interface surface including;

human-readable information relating to the computer software; and

coded data indicative of at least one interactive element relating to the computer software, the information and coded data having been printed substantially simultaneously onto a substrate to form the interface surface; and

a sensing device that generates, using coded data sensed in response to placing the sensing device in an operative position relative to the interface surface, indicating data indicative of the at least one interactive element and movement of the sensing device relative to the interface surface;

the system including a computer system running the computer software, wherein the computer system;

(a) receives the indicating data from the sensing device;

(b) determines movement of the sensing device relative to the interface surface using the indicating data;

(c) identifies the at least one interactive element from the indicating data; and

(d) operates the computer software at least partly in reliance on the movement, and in accordance with instructions associated with the at least one interactive element.

94. A system according to claim 93, wherein the interactive element is a hyperlink element relating to the computer software, the computer system being configured to effect an operation associated with the hyperlink element.

95. A system according to claim 94, wherein the computer system is configured to send, to the computer software, data indicative of the hyperlink element.

96. A system according to claim 93, the computer being configured to send, to the computer software, data indicative of a name and/or value of at least one field related to the computer software.

97. A system according to claim 93, the computer being configured to send, to the computer software, data indicative of a selected object.

98. A system according to claim 93, wherein the interactive element is a checkbox field relating to the computer software, the computer system being configured to:

identify that the user has entered a hand-drawn mark by means of the sensing device; and

effect an operation associated with the checkbox field.

99. A system according to claim 98, wherein the computer system is configured to associate a true value with the checkbox field.

100. A system according to 99, wherein the computer system is configured to send data to the computer software indicative of at least the checkbox field.

101. A system according to claim 93, wherein the interactive element is a text field relating to the computer software, the computer system being configured to:

identify that the user has entered handwritten text data by means of the sensing device; and

effect an operation associated with the text field.

102. A system according to claim 101, the computer system being configured to convert the handwritten text data to computer text.

103. A system according to 102, the computer system being configured to associate the computer text with the text field.

104. A system according to claim 102, the computer system being configured to send data to the computer software indicative of at least the text field.

105. A system according to claim 93, wherein the interactive element is a signature field relating to the computer software, the computer system being configured to:

identify that the user has entered a handwritten signature by means of the sensing device; and

effect an operation associated with the signature field.

106. A system according to claim 105, the computer system being configured to send, to the computer software, data indicative of at least the signature field.

107. A system according to claim 105, the computer system being configured to verify that the signature is that of the user.

108. A system according to claim 107, the computer system being configured to use a signature key associated with the user to generate a digital signature of at least data indicative of a name and/or value of at last one field related to the computer software.

109. A system according to claim 108, the computer system being configured to associate the digital signature with the signature field.

110. A system according to claim 93, wherein the interactive element is a drawing field related to the computer software, the computer system being configured to:

identify that the user has entered a hand-drawn picture by means of the sensing device; and

effect an operation associated with the drawing field.

111. A system according to claim 110, the computer system being configured to send, to the computer software, data indicative of at least the drawing field.

112. A system according to any claim 93, further including the sensing device, wherein the sensing device includes a marking nib.

113. A system according to claim 93, further including the sensing device, wherein the sensing device contains identifying data indicative of an identity of the user.

114. A system according to claim 113, the computer system being configured to monitor the identifying data when the sensing device is in use.

115. A system according to 93, the computer system including a printer to print the information onto the interface surface on demand prior to use of the sensing device to sense the indicating data.

116. A system according to claim 115, wherein the printer includes a binding mechanism for binding multiple interface surfaces, defined by multiple corresponding pages, into a bound document.

117. A system according to claim 93, wherein the coded data is substantially invisible to an unaided human eye.

118. A system according to claim 93, the computer system being configured to retain a retrievable record of each interface surface printed, the interface surface being retrievable using the identity contained in its associated coded data.

119. A system according to claim 93, the information being sufficiently detailed in relation to the computer software that a user can interact with the computer system without the need for a separate display device.

120. A system according to claim 93, the system being configured to distribute a plurality of the interface surfaces using a mixture of multicast and pointcast communications protocols.

121. A system according to claim 93, wherein the coded data includes at least one tag, each tag being indicative of the interactive element.

122. A system according to claim 121, wherein each of the tags include identity data defining the at least one interactive element.

123. A system according to claim 121, wherein the surface is defined by a substrate.

124. A system according to claim 123, wherein the substrate is laminar.

125. A system according to claim 121, wherein the tags are disposed at predetermined positions on the surface.

126. A system according to claim 125, wherein the tags are disposed on the surface within a tessellated pattern comprising a plurality of tiles, each of the tiles containing a plurality of the tags.

127. A system according to claim 126, wherein the tiles interlock with each other to substantially cover the surface.

128. A system according to claim 127, wherein the tiles are all of a similar shape.

129. A system according to claim 128, wherein the tiles are triangular, square, rectangular or hexagonal.

130. A system according to claim 126, wherein the tags are disposed stochastically within each of the tiles.

131. A system according to claim 121, wherein each of the tags includes at least one common feature in addition to the identity data.

132. A system according to claim 131, wherein one or more common features are configured to assist finding and/or recognition of the tags by associated tag reading apparatus.

133. A system according to claim 131, wherein the one or more common features are represented format incorporating redundancy of information.

134. A system according to claim 133, wherein the at least one common feature is rotationally symmetric so as to be rotationally invariant.

135. A system according to claim 133, wherein the at least one common feature is ring-shaped.

136. A system according to claim 121, wherein each of the tags includes at least one orientation feature for enabling a rotational orientation of the tag being read to be ascertained.

137. A system according to claim 136, wherein the at least one orientation feature is represented in a format incorporating redundancy of information.

138. A system according to claim 137, wherein the at least one orientation feature is rotationally asymmetric.

139. A system according to claim 137, wherein the at least one orientation feature is skewed along its major axis.

140. A system according to claim 121, wherein each of the tags includes at least one perspective feature for enabling a perspective distortion of the tag being read to be ascertained.

141. A system according to claim 140, wherein the at least one perspective feature includes at least four sub-features, the relative positions of which define a non-degenerate quadrilateral.

142. A system according to claim 121, wherein each tag includes a plurality of tag elements, the first and second identity data each being defined by a plurality of the elements.

143. A system according to claim 142, wherein the tag elements are disposed in one or more arcuate bands around a central region of each tag.

144. A system according to claim 143, wherein there are a plurality of the arcuate bands disposed concentrically with respect to each other.

145. A system according to claim 142, wherein each element takes the form of a dot having a plurality of possible values.

146. A system according to claim 145, wherein the number of possible values is two.

147. A system according to claim 145, wherein when representing one of the possible values, the tag elements absorb, reflect or fluoresce electromagnetic radiation of a predetermined wavelength or range of wavelengths to a predetermined greater or lesser extent than the surface.

148. A system according to claim 145, wherein the possible values of the tag elements are defined by different relative absorption, reflection or fluorescence of electromagnetic radiation of a predetermined wavelength or range of wavelengths.

149. A system according to claim 145, wherein the tags are not substantially visible to an average unaided human eye under daylight or ambient lighting conditions.

150. A system according to claim 145, wherein the tags are slightly visible to an average unaided human eye under daylight or ambient lighting conditions.

151. A system according to claim 145, wherein the tags are visible to an average unaided human eye under daylight or ambient lighting conditions.

152. A system according to claim 121, wherein the first identity data is represented in a format incorporating redundancy of information.

153. A system according to claim 121, wherein the second identity data is represented in a format incorporating redundancy of information.

154. A system according to claim 121, wherein the tags are printed onto the surface by means of a printer.

155. A system according to claim 154, wherein the printer is an ink printer.

156. A system according to claim 155, wherein the tags are printed using ink that is absorbent or reflective in the ultraviolet spectrum or the infrared spectrum.

157. A system according to claim 154, wherein the printer also prints additional information onto the surface.

158. A system according to claim 157, wherein the additional information is printed onto the surface using colored or monochrome inks.

159. A system according to claim 158, wherein the additional information is printed onto the surface using one of the following combinations of colored inks:

CMY;

CMYK;

CMYRGB; and

spot colour.

160. A system according to claim 121, wherein at least a plurality of the tags are disposed stochastically upon the surface.

161. A system according to claim 121, wherein the tags are disposed in a regular array on the surface.

162. A system according to claim 161, wherein the array is triangular.

163. A system according to claim 161, wherein the array is rectangular.

164. A system according to claim 161, wherein the tags are tiled over the surface.

165. A system according to claim 121, further including additional non-tag information disposed on the surface.

166. A system according to claim 93, wherein the region is identified with sufficient precision to distinguish the region from 1.5×

10¹⁴ other regions.

167. A system according to claim 93, wherein any 10 millimeter diameter subregion of the region includes sufficient information to identify the region.

168. A system according to claim 167, wherein any 10 millimeter subregion of the region includes sufficient information to identify at least one point of the region.

169. A system according to claim 93, wherein the sensing device includes at least one acceleration measuring device for measuring acceleration of the sensing device as it is used to draw the user input onto the surface, wherein step (b) includes the substep of periodically sampling the acceleration of the sensing device as it is used to draw the user input onto the surface, and step (d) includes the substep of:

(i) ascertaining a locus of the sensing means in relation to the surface by ascertaining relative displacement of the sensing device due to its velocity within each sampling period.

170. A system according to claim 169, wherein the accelerometers are configured to measure at least two orthogonal components of acceleration.

171. A system according to claim 93, the printed information including position elements, the position elements being disposed on a surface, wherein step (b) includes the substep of periodically sensing the position elements with the sensing device as it is used to draw the user input onto the surface, and step (d) includes the substep of:

(i) ascertaining a locus of the sensing means in relation to the surface by ascertaining relative displacement of the sensing means with respect to the position elements during periods between reading thereof.

172. A system according to claim 171, wherein the position elements are disposed on the surface as a regular array of dots, lines or other formations.

173. A system according to claim 171, wherein the position elements are disposed on the surface stochastically.

174. A system according to claim 93, wherein step (d) includes the substep of:

(i) ascertaining a locus of the sensing means in relation to the surface by ascertaining relative movement of one or more motion sensing elements rotatably mounted to the sensing device for contact with the surface while the sensing device is used to draw the user input thereon.

175. A system according to claim 174, wherein the motion sensing elements include one or more rollerballs mounted for free rotation within a constraining housing disposed substantially within the sensing device.

176. A system according to claim 175, wherein substep (d)(i) includes the substep of periodically measuring components of rotation of the rollerball due to movement of the sensing device by the user when drawing the user input onto the surface.

177. A system according to claim 176, wherein the components of rotation of the rollerball due to movement of the sensing device by the user when drawing the user input onto the surface are measured by means of:

rollers disposed within the constraining housing for rotation driven by contact with the rotating rollerball;

or

optical sensing of rotation of the rollerball with respect to the constraining housing.

178. A system according to claim 93, wherein the movement includes at least one stroke.

179. A system according to claim 93, wherein a stroke is initialised when the pen is placed in an operative position relative to the interface surface and is completed when the pen is removed from the operative position.

180. A system according to claim 93, wherein the indicating data is indicative of a sequence of pen positions, the pen positions being determined by sensing of the coded data.

181. A system according to claim 180, wherein the indicating data is further indicative of the relative time at which each pen position is determined.

182. A system according to claim 93, wherein the indicating data is indicative of a number of strokes, each stroke being represented by a respective sequence of pen positions.

183. A system according to claim 182, wherein each stroke is further represented by an identifier indicative of an identity of the interface surface.

184. A system according to claim 182, the number of strokes representing handwritten text.