Pointing device utilizing a photodetector array
First Claim
Patent Images
1. An optical detection system comprising:
- an aperture;
a lens positioned near said aperture, for receiving a light signal reflected from a surface and though said aperture, for focusing said light signal to form a focused light signal;
a fist detection system for detecting displacement along a first dimension, comprising;
a comb pbotodetector array, optically matched with said lens and said aperture, for receiving said focused light signal, said focused light signal having light and dark portions representing a pattern caused by said light signal reflecting off of the surface, said comb photodetector having first, second, third, fourth, fifth, sixth, seventh, and eighth elements, said first and fifth elements are coupled to generate a first comb signal, said second and sixth elements are coupled to generate a second comb signal, said third and seventh elements are coupled to generate a third comb signal, and said fourth and eighth elements are coupled to generate a fourth comb signal;
a generation unit, for combining said first and second comb signals to generate a first quasi-sinusoidal signal, for combining said third and fourth comb signals to generate a second quasi-sinusoidal signal, wherein said first and second quasi-sinusoidal signals are analog quasi-sinusoidal signals;
a displacement detection unit, for determining a frequency of said first and second sinusoidal signals, said frequency of said first sinusoidal signal representing a displacement of said pattern along said first dimension, said frequency of said second sinusoidal signal representing a direction of said displacement of said pattern along said first dimension.
1 Assignment
0 Petitions
Accused Products
Abstract
An optical detection system particularly suited to us as a pointing device uses a photodetector array capable of generating a quasi-sinusoidal signal in response to illumination with an image of appropriate size. The detection system can use either coherent or non-coherent light, and existing textures in standard materials such as paper or printed patterns.
199 Citations
20 Claims
-
1. An optical detection system comprising:
-
an aperture; a lens positioned near said aperture, for receiving a light signal reflected from a surface and though said aperture, for focusing said light signal to form a focused light signal; a fist detection system for detecting displacement along a first dimension, comprising; a comb pbotodetector array, optically matched with said lens and said aperture, for receiving said focused light signal, said focused light signal having light and dark portions representing a pattern caused by said light signal reflecting off of the surface, said comb photodetector having first, second, third, fourth, fifth, sixth, seventh, and eighth elements, said first and fifth elements are coupled to generate a first comb signal, said second and sixth elements are coupled to generate a second comb signal, said third and seventh elements are coupled to generate a third comb signal, and said fourth and eighth elements are coupled to generate a fourth comb signal; a generation unit, for combining said first and second comb signals to generate a first quasi-sinusoidal signal, for combining said third and fourth comb signals to generate a second quasi-sinusoidal signal, wherein said first and second quasi-sinusoidal signals are analog quasi-sinusoidal signals; a displacement detection unit, for determining a frequency of said first and second sinusoidal signals, said frequency of said first sinusoidal signal representing a displacement of said pattern along said first dimension, said frequency of said second sinusoidal signal representing a direction of said displacement of said pattern along said first dimension. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
-
-
12. An method for detecting movement of a pattern across a photodetector array, comprising the steps of:
-
receiving a light signal at the photodetector array, said light signal reflected off of a surface and passing though an aperture and a lens, said photodetector array optically matched with said lens and said aperture, said light signal having light and dark portions representing a pattern caused by said light signal reflecting off of the surface said photodetector array having first, second, third, fourth, fifth, sixth, seventh, and eighth elements; combining a signal from said first and fifth elements to generate a first comb signal; combining a signal from said second and sixth elements to generate a second comb signal; combining a signal from said third and seventh elements to generate a third comb signal; combining a signal from said fourth and eighth elements to generate a fourth comb signal; combining said first and second comb signals to generate a first quasi-sinusoidal signal; combining said third and fourth comb signals to generate a second quasi-sinusoidal signal, wherein said first and second quasi-sinusoidal signals are analog quasi-sinusoidal signals; and determining a frequency of said first and second sinusoidal signals, said frequency of said first sinusoidal signal representing a displacement of said pattern along a first dimension, said frequency of said second sinusoidal signal representing a direction of said displacement of said pattern along said first dimension. - View Dependent Claims (13, 14, 15, 16, 17, 18, 19)
-
-
20. An method for detecting movement of a pattern across a photo detection means, comprising:
-
photo detection means, for receiving a light signal reflected off of a surface and passing through an aperture and a lens, said photodetector means optically matched with said lens and said aperture, said light signal having light and dark portions representing a pattern caused by said light signal reflecting off of a surface, said photodetector means having a plurality of elements; first combining means, for combining a signal from said first and fifth elements to generate a first comb signal, for combining a signal from said second and sixth elements to generate a second comb signal, for combining a signal from said third and seventh elements to generate a third comb signal and for combining a signal from said fourth and eighth elements to generate a fourth comb signal; second combining means, for combining said first and second comb signals to generate a first quasi-sinusoidal signal; third combining means, for combining said third and fourth comb signals to generate a second quasi-sinusoidal signal, wherein said first and second quasi-sinusoidal signals arc quasi-sinusoidal signals; and determining means, for determining a frequency of said first and second sinusoidal signals, said frequency of said first sinusoidal signal representing a displacement of said pattern along a first dimension, said frequency of said second sinusoidal signal representing a direction of said displacement of said pattern along said first dimension.
-
Specification