Position detection apparatus using area image sensor
First Claim
1. A position detection apparatus for detecting a pointing device being situated on a detection plane, said position detection apparatus comprising:
- a pair of imaging sections, each imaging section comprising an area image sensor in which light-sensitive elements are arrayed in a two-dimensional pattern to produce a two-dimensional image of pixels, and an image formation lens, and the pair of the imaging sections image an area over the detection plane in a given field of view from two lateral sides of the detection plane to output an image signal corresponding to all pixels of the given field of view, wherein the two-dimensional image includes a two-dimensional space that is both parallel to the detection plane and perpendicular to the detection plane;
marker means disposed to at least four peripheral corners of the detection plane and each functioning as a reference for defining a particular field of view along a distortion of the detection plane within a range of the given field of view to be imaged by the imaging sections;
a selection means utilizing the image signal as an input to select particular pixels as a portion of all of the pixels in the two dimensional space along the distortion of the detection plane, corresponding to the particular field of view within the range of the given field of view from the light-sensitive elements, only the particular pixels of the particular field of view configured for processing, the particular pixels comprising;
a first row of a plurality of pixels parallel to the detection plane; and
a second row of a plurality of pixels parallel to the detection plane, the second row being different from the first row, wherein the second row of the plurality of pixels comprises a number of pixels different from a number of pixels for the first row of the plurality of pixels; and
an image processing means, which utilizes a particular image signal corresponding to the particular pixels having been selected by the selection means as an input to execute the image processing, thereby outputting a coordinate of an indicating position on the detection plane indicated by the pointing device.
4 Assignments
0 Petitions
Accused Products
Abstract
A position detection apparatus, with which the setting position adjustment of imaging sections is not required and the maintenance can be made easily, structuring of which can be realized with low-cost components, is provided. In the position detection apparatus, imaging sections (7), each of those which includes an area image sensor (70), in which light-sensitive elements are arrayed in a two-dimensional pattern, and an image formation lens (71), are placed to the lateral two points of a detection plane (1), respectively. A selection device (10) selects particular pixels corresponding to a particular field of view of a reflex reflection frame (4) or the like from the light-sensitive elements within a range of a given field of view having been imaged by the imaging sections (7). An image processing device (11) image-processes a particular image signal corresponding to the selected particular pixels and then outputs an indicating position coordinate of a pointing device (2).
50 Citations
19 Claims
-
1. A position detection apparatus for detecting a pointing device being situated on a detection plane, said position detection apparatus comprising:
-
a pair of imaging sections, each imaging section comprising an area image sensor in which light-sensitive elements are arrayed in a two-dimensional pattern to produce a two-dimensional image of pixels, and an image formation lens, and the pair of the imaging sections image an area over the detection plane in a given field of view from two lateral sides of the detection plane to output an image signal corresponding to all pixels of the given field of view, wherein the two-dimensional image includes a two-dimensional space that is both parallel to the detection plane and perpendicular to the detection plane; marker means disposed to at least four peripheral corners of the detection plane and each functioning as a reference for defining a particular field of view along a distortion of the detection plane within a range of the given field of view to be imaged by the imaging sections; a selection means utilizing the image signal as an input to select particular pixels as a portion of all of the pixels in the two dimensional space along the distortion of the detection plane, corresponding to the particular field of view within the range of the given field of view from the light-sensitive elements, only the particular pixels of the particular field of view configured for processing, the particular pixels comprising; a first row of a plurality of pixels parallel to the detection plane; and a second row of a plurality of pixels parallel to the detection plane, the second row being different from the first row, wherein the second row of the plurality of pixels comprises a number of pixels different from a number of pixels for the first row of the plurality of pixels; and an image processing means, which utilizes a particular image signal corresponding to the particular pixels having been selected by the selection means as an input to execute the image processing, thereby outputting a coordinate of an indicating position on the detection plane indicated by the pointing device. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 18)
-
-
13. A position detection apparatus for detecting a pointing device being situated on a detection plane, the position detection apparatus comprising:
-
a pair of imaging sections, each of those which includes an area image sensor, in which light-sensitive elements are arrayed in a two-dimensional pattern to produce a two-dimensional image, and an image formation lens, and images an area over the detection plane in a given field of view from two lateral sides of the detection plane to output an image signal corresponding to all light-sensitive elements of the given field of view, wherein the two-dimensional image includes a two-dimensional space that is both parallel to the detection plane and perpendicular to the detection plane; marker means each functioning as a reference for defining a particular field of view along a distortion of the detection plane within a range of the given field of view to be imaged by the imaging sections, the marker means comprising at least one of the following two structures;
a light reflection member and a light-emitting source;an image processing means that utilizes the image signal being outputted from the imaging sections as an input, defines a given part of the image signal on the basis of a line forming images of the marker means, and uses the image signal of the given part having been defined to work out a coordinate of an indicating position on the detection plane being indicated by a pointing device; the given part of the image signal comprising a configuration of a portion of the plurality of the light-sensitive elements in the two-dimensional space along the line, only the configuration of the light-sensitive elements are utilized for detecting a pointing device, the configuration comprising; a first row of a plurality of light-sensitive elements parallel to the detection plane; and a second row of a plurality of light-sensitive elements parallel to the detection plane, the second row being different from the first row, wherein the second row of the plurality of light-sensitive elements comprises a number of light-sensitive elements different from a number of light-sensitive elements for the first row of the plurality of light-sensitive elements; and a follow-up means for detecting the changes in the positions of the marker means either automatically at a given interval or manually at operator'"'"'s option to renewedly define the given part. - View Dependent Claims (19)
-
-
14. A position detection apparatus comprising:
-
a detection plane; an imaging system positioned relative to the detection plane and comprising a field of view for imaging that includes the detection plane and an area over the detection plane, the imaging system producing a two-dimensional image of the field of view; and an image processing system coupled to the imaging system and comprising the capability to periodically; activate the imaging system to image the orientation of the detection plane relative to the area over the detection plane; determine if the orientation of the detection plane relative to the area over the detection plane has changed; and adjust the field of view of the imaging system in response to a determination that the orientation of the detection plane has changed relative to the area over the detection plane, wherein the field of view comprises a plurality of rows of pixels extending perpendicular to the detection plane with each row being parallel to the detection plane, and wherein the image processing system is configured to utilize only a subset of the plurality of rows of pixels selected according to the orientation of the detection plane for a detection process to output a coordinate of an indicating position on the detection plane, the subset comprising; a first row of a plurality of pixels; and a second row of a plurality of pixels, the second row being different from the first row and comprising a number of pixels different from a number of pixels for the first row of the plurality of pixels. - View Dependent Claims (15, 16)
-
-
17. A method for detecting a position of a pointing device relative a detection plane, said method comprising:
-
providing a position detection apparatus comprising; a detection plane; an imaging system positioned relative to the detection plane and comprising a field of view for imaging that includes the detection plane and an area over the detection plane, the imaging system producing a two-dimensional image of the field of view; and an image processing system coupled to the imaging system and configured to process images provided by the imaging system; utilizing the image processing system to periodically activate the imaging system to image the orientation of the detection plane relative the area over the detection plane; utilizing the image processing system to periodically determine if the orientation of the detection plane relative to the area over the detection plane has changed; and utilizing the image processing system to periodically adjust the field of view of the imaging system in response to a determination that the orientation of the detection plane has changed relative to the area over the detection plane wherein the field of view comprises a plurality of rows of pixels extending perpendicular to the detection plane with each row being parallel to the detection plane, and wherein the image processing system is configured to utilize only a subset of the plurality of rows of pixels selected according to the orientation of the detection plane for a detection process to output a coordinate of an indicating position on the detection plane, the subset comprising; a first row of a plurality of pixels; and a second row of a plurality of pixels, the second row being different from the first row and comprising a number of pixels different from a number of pixels for the first row of the plurality of pixels.
-
Specification