×

Optical position detecting unit and optical coordinate input unit

  • US 5,572,251 A
  • Filed: 10/28/1994
  • Issued: 11/05/1996
  • Est. Priority Date: 03/17/1994
  • Status: Expired due to Fees
First Claim
Patent Images

1. An optical position detecting unit for optically detecting a position of a freely movable light point comprising:

  • an image sensor having a pixel array region configured by a relatively small number of pixels;

    an imaging lens for forming an image of said light point at a position in front of the pixel array region of said image sensor;

    a converging lens disposed between said image sensor and the position of the image of said light point on an optical axis of said imaging lens for converging light coming from said light point onto the pixel array region of said image sensor, the light passing through the image of said light point;

    a transparent optical pattern plate having a pattern containing optical code information uniquely corresponding to the position of said light point on the screen, the plate being disposed between said converging lens and the position of the image of said light point in a plane parallel with the pixel array region of said image sensor, the code information pattern enabling the position of said light point to be determined by means of optical codes included in a region through which the light from said light point passes, said optical codes in the region being projected onto the pixel array region by the converging light coming from said light point onto the pixel array region; and

    signal processing means for processing signals outputted from said image sensor on which said codes are projected onto said pixel array region so as to extract information of the position of said light point by using said codes.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×