OPTICAL ELEMENTS WITH ALTERNATING REFLECTIVE LENS FACETS

• US 20120176343A1
• Filed: 03/20/2012
• Published: 07/12/2012
• Est. Priority Date: 11/02/2001
• Status: Active Grant

• Current Assignee: Neonode, Inc.
• Original Assignee: Neonode, Inc.
• Inventors: Sparf, Lars, Goertz, Magnus, Eriksson, Thomas, Shain, Joseph, Jansson, Anders, Kvist, Niklas, Pettersson, Robert, Karlsson, John, Holmgren, Stefan
• Granted Patent: US 9,052,777 B2
• Time in Patent Office: Days
• US Class Current: 345/175
• CPC Class Codes: G06F 2203/04808 Several contacts: gestures triggering a specific function, e.g. scrolling, zooming, right-click, when the user establishes several contacts with the surface simultaneously; e.g. using several fingers or a combination of fingers and pen
• CPC Class Codes: G06F 3/042 by opto-electronic means
• CPC Class Codes: G06F 3/0421 by interrupting or reflecting a light beam, e.g. optical touch-screen
• CPC Class Codes: G06F 3/0425 using a single imaging device like a video camera for tracking the absolute position of a single or a plurality of objects with respect to an imaged reference surface, e.g. video camera imaging a display or a projection screen, a table or a wall surface, on which a computer generated image is displayed or projected tracking a projected light spot to determine a position on a display surface G06F3/0386
• CPC Class Codes: G06F 3/0428 by sensing at the edges of the touch surface the interruption of optical paths, e.g. an illumination plane, parallel to the touch surface which may be virtual sensing beam interruptions in a planar beam grid of an optical touch-screen G06F3/0421
• CPC Class Codes: G06F 3/04883 for inputting data by handwriting, e.g. gesture or text

Abstract

An optical element for a light based touch surface including a concatenated plurality of segments, wherein each segment is paired with a respective light emitter, each segment including an undulating series of pairs of reflective or refractive facets, wherein a first facet in each pair is oriented so as to collimate light emitted from a first light emitter associated with the segment and a second facet in each pair is oriented so as to collimate light emitted from a second light emitter associated with the segment, and wherein the first light emitter associated with the segment is the light emitter paired with the segment and the second light emitter associated with the segment is the light emitter paired with a neighboring segment.

Claims

1. An optical element for a light based touch surface comprising a concatenated plurality of segments, wherein each segment is paired with a respective light emitter, each segment comprising an undulating series of pairs of reflective or refractive facets, wherein a first facet in each pair is oriented so as to collimate light emitted from a first light emitter associated with the segment and a second facet in each pair is oriented so as to collimate light emitted from a second light emitter associated with the segment, and wherein the first light emitter associated with the segment is the light emitter paired with the segment and the second light emitter associated with the segment is the light emitter paired with a neighboring segment.

2. The optical element of claim 1, wherein, for each of said plurality of segments, light emitted from the first light emitter associated with the segment is directed by the segment to generate a first local spatial light intensity distribution of collimated light beams across an area of the touch surface, and light emitted from the second light emitter associated with the segment is directed by the segment to generate a second local spatial light intensity distribution of collimated light beams across the area of the touch surface, and wherein the first and second local spatial light intensity distributions are different distributions.

3. The optical element of claim 2 wherein, for each of said plurality of segments, a first plurality of the first facets of its series of facet pairs, near the first light emitter associated with the segment, comprise sizes that decrease as a function of the first facet'"'"'s distance from the first light emitter, and a second plurality of the first facets, further from the first light emitter, comprise sizes that increase as a function of the first facet'"'"'s distance from the first light emitter, such that the first local spatial light intensity distribution is substantially linear as a function of spatial position.

4. A modular component for a light based touch surface assembly, comprising:

at least one of said plurality of segments of the optical element of claim 1 and the light emitters paired therewith in a single unit; and

two oppositely contoured outer edges, to facilitate inter-fitting the modular component with a similar neighboring modular component that contains a segment adjacent to one of the segments comprised in the modular component, by positioning one of the contoured outer edges of the modular component alongside the oppositely contoured outer edge of the neighboring modular component.

5. An optical touch detection system, comprising:

a housing;

a surface mounted in said housing;

a set of first optical elements in accordance with claim 1 positioned along one edge of said surface;

the light emitters paired with the segments of said set of first optical elements, mounted in said housing;

a set of second optical elements positioned along an edge of said surface opposite the one edge, comprising a concatenated plurality of like segments, wherein each segment is paired with a respective light receiver, each segment comprising an undulating series of pairs of reflective or refractive facets, wherein a first facet in each pair directs collimated light to a first light receiver associated with the segment and a second facet in each pair directs collimated light to a second light receiver associated with the segment, and wherein the first light receiver associated with the segment is the light receiver paired with the segment and the second light receiver associated with the segment is the light receiver paired with a neighboring segment;

the light receivers paired with the segments of said set of second optical elements, mounted in said housing; and

a calculating unit, mounted in said housing and connected to said light receivers, for determining a location of a pointer touching said surface, based on amounts of light emitted from said light emitters that is blocked by the pointer, as determined by outputs of said light receivers.

6. The optical touch screen of claim 5 wherein, for each of said plurality of segments of said set of first optical elements, the collimated light directed by the first facets of each of the series of facet pairs of the segment at least partially overlap with the collimated light directed by the second facets, and wherein said calculating unit determines the location of the pointer touching the surface based on outputs of at least three light receivers that receive light emitted by three neighboring light emitters.

7. The optical touch screen of claim 5, wherein the segments of said set of first optical elements do not all have the same length, and the segments of said set of second optical elements do not all have the same length.

8. The optical touch screen of claim 5, further comprising a set of third optical elements in accordance with claim 1, arranged along an edge of said surface adjacent to said one edge, wherein one of the segments of one of said set of first optical elements and one of the segments of one of said set of third optical elements are paired with the same emitter.

9. An optical element for a light based touch surface, comprising a concatenated plurality of segments, wherein alternating ones of said segments are respectively paired with alternating light emitters and light receivers, each segment comprising an undulating series of pairs of reflective or refractive facets, wherein a first facet in each pair is oriented so as to collimate light emitted from a light emitter associated with the segment, and a second facet in each pair is oriented so as to direct collimated light onto a light receiver associated with the segment, and wherein the light receiver associated with the segment is one of the light receivers that neighbor the light emitter associated with the segment.

10. The optical element of claim 9 wherein, for each of said plurality of segments, light emitted from the light emitter associated with the segment is directed by the segment to generate a local spatial light intensity distribution of collimated light beams across an area of the touch surface, wherein a first plurality of the first facets of its series of facet pairs, near the light emitter associated with the segment, comprise sizes that decrease as a function of the first facet'"'"'s distance from the light emitter, and a second plurality of the first facets, further from the light emitter, comprise sizes that increase as a function of the first facet'"'"'s distance from the light emitter, and wherein the local spatial light intensity distribution is substantially linear as a function of spatial position.

11. A modular component for a light based touch surface assembly, comprising:

at least one of said plurality of segments of the optical element of claim 9 and the light emitters and receivers paired therewith in a single unit; and

two oppositely contoured outer edges, to facilitate inter-fitting the modular component with a similar neighboring modular component that contains a segment adjacent to one of the segments comprised in the modular component, by positioning one of the contoured outer edges of the modular component alongside the oppositely contoured outer edge of the neighboring modular component.

12. An optical touch detection system, comprising:

a housing;

a surface mounted in said housing;

a frame of optical elements in accordance with claim 9, surrounding said surface;

the alternating plurality of light emitters and light receivers paired with the segments in the optical elements of said first frame, mounted in said housing; and

a calculating unit mounted in said housing and connected to said light receivers to determine the location of an object on said surface based on amounts of light emitted from said emitters that is blocked by the pointer, as determined from outputs of said light receivers.

13. The optical touch detection system of claim 12, further comprising a frame of lenses inside said frame of optical elements, each of said lenses comprising a pattern of recessed cavities formed by a repetitive pattern of three substantially planar facets, for refracting collimated light emitted by said emitters in three directions and for directing collimated beams from three directions onto said receivers.

14. The optical touch detection system of claim 13, wherein said calculating unit determines the locations of at least two objects that are on said surface simultaneously.

15. The optical touch detection system of claim 13, wherein said calculating unit determines the locations of at least three non-aligned objects that are on said surface simultaneously.

16. The optical touch detection system of claim 13, wherein said calculating unit determines the locations of at least four non-aligned objects that are on said surface simultaneously.

17. The optical touch detection system of claim 13, wherein said calculating unit determines the location of a stylus on said surface, the stylus being held by a user, when the user'"'"'s palm blocks some of the light emitted from said emitters from reaching the stylus.