Patent ID: 6181367
Filing Date: 2001-01-30
Classification: G02B,G02F,G09F

Abstract:
A image displaying system comprising: an image displaying device, comprisinga first plate comprised of a transparent material and having a first refractive index,a light generator selectively directing light beams into the first plate at a plurality of respective locations along a surface of the first plate, the light beam being directed into the first plate in a manner that causes the light beams to propagate along the first plate with total internal reflection in the first plate;an index of refraction modulator positioned adjacent the first plate, the index of refraction modulator having a plurality of modulating elements at respective areas spaced apart from each other in the first direction, each of the modulating elements being selectively controllable to either a first refractive index state or a second refractive index state responsive to a respective control signal, the first refractive index state causing the modulating element to have an index of refraction that is sufficiently lower than the index of refraction of the first plate to cause the light beam to remain internally reflected in the first plate in the area of the modulating element, and the second refractive index state causing the modulating element to have an index of refraction that is sufficiently high to allow the light beam to exit the first plate in the area of the modulating element; andan optical element positioned adjacent the index of refraction modulator, the optical element controlling the angle of divergence in the first direction of light exiting the first plate in the area of the modulating element; andan electronic system for providing signals to the light generator and the index of refraction modulator corresponding to a video signal having a plurality of video lines in each video image frame, the electronic system comprising:a light control circuit coupled to the light generator, the light control circuit causing the intensity of light generated by the light generator at each location to correspond to the amplitude of the video signal at a corresponding point during each video line; anda refractive index modulator control circuit coupled to the index of refractive index modulator, the refractive index modulator control circuit applying a control signal to the index of refraction modulator to selectively cause each of the modulating elements to be in the second refractive index state responsive to a corresponding video line in each video image frame of the video signal.