Abstract: An invalid frame in 60P images supplied from a 60P camera head is delayed by a single frame by a 1-frame delay circuit. A differential between the delayed invalid frame and the valid frame is computed by a subtracting circuit. Of the differential signal, only a portion over a predetermined value is picked out by a level filter. The picked out signal is attenuated to ½ by a ½ attenuator. By adding that attenuated signal to the valid frame by an adder, the invalid frame is superimposed on that valid frame. As a result, a natural picture is obtained.

Abstract: An optical image pickup device applicable to composite picture without the use of chromakey composition technique is presented.

Abstract: The present invention provides a video projector equipped with a projection lens system having only one optical axis for projecting a plurality color images displayed on a plurality of CRTs. The color images displayed on the CRTs 2R, 2B and 2G are respectively focused onto a writing side of respective spatial light modulators 4R, 4G and 4B through a plurality of writing lens 3R, 3G and 3B. On the other hand, a light from a reading light source 5 is divided into 3-color lights of R, G and B by a cross-type 3-color separation member 25. The three color lights are respectively inputted into a reading side of the respective spatial light modulators through a plurality of polarization beam splitter blocks 26R, 26G and 26B each having a pair of dielectric multiple layers 26a, 26b disposed parallel to each other.

Abstract: An optical IC-type head assembly for recording and for reading information on an optical disc, comprising a substrate, a light guiding layer comprising a dielectric thin film formed monolithically on the substrate, a laser oscillator for injecting the laser beam into the light guiding layer, a grating coupler for converging the laser beam on the optical disc, and a photo detector for receiving the beam reflected by the optical disc and coming out of the grating coupler. In one embodiment the substrate is made of material having cleavability. One side surface of the light guiding layer receiving the laser beam is a break surface formed by cleaving the substrate along the cleavage plane. The photo detector is disposed at the break surface of the light guiding layer. The substrate is preferably made of single crystal material.

Abstract: A three tube type color television camera comprises an optical system using a prism for the three color separation in which an image of a test pattern is introduced into an optical path of the camera through the optical system. The optical system has an incident plane onto which the image of the test pattern is projected by a pattern projector closely located with respect to the incident plane.

Abstract: An optical IC-type head assembly for recording and for reading information on an optical disc, comprising a substrate, a light guiding layer comprising a dielectric thin film formed monolithically on the substrate, a laser oscillator for injecting the laser beam into the light guiding layer, a grating coupler for converging the laser beam on the optical disc, and a photo detector for receiving the beam reflected by the optical disc and coming out of the grating coupler. In one embodiment the substrate is made of material having cleavability. One side surface of the light guiding layer receiving the laser beam is a break surface formed by cleaving the substrate along the cleavage plane. The photo detector is disposed at the break surface of the light guiding layer. The substrate is preferably made of single crystal material.

Abstract: A zoom lens apparatus comprises sensors for detecting relative positions of a variable power lens group and a compensating lens group, a memory for pre-storing compensating data peculiar to the zoom lens apparatus, a control circuit and driving parts for moving the variable power lens group and the compensating lens group. The control circuit compares position data set by a variable power setting operation and position data obtained from the sensors and outputs signals for controlling the relative positions of the variable power lens group and the compensating lens group based on the compensating data read out from the memory. The driving parts vary the relative positions of the variable power lens group and the compensating lens group responsive to the output signals of the control circuit.

Abstract: An optical head assembly for recording information on an optical disc or for taking out information already recorded, the optical head assembly including a semiconductor substrate and a dielectric light conducting layer formed on the substrate, the light conducting layer being internally formed with optical elements for converging laser beam from a laser beam source onto the optical disc and directing the reflected beam from the optical disc surface toward a photo detector. Output signal from the photo detector is used for reading information and also for allowing the optical head assembly to trace a track on the optical disc.

Abstract: A focusing error detecting device used in a head assembly for recording information to a recording surface of an optical disc or reading out information already recorded, the focusing error detecting device including a diffraction grating for focusing light which has been introduced from a light source into a thin-film waveguide layer, onto the recording surface, and two light receiving diffraction gratings for conducting the light reflected by the recording surface again into the waveguide layer. The two light receiving diffraction gratings have optical characteristics which differ from each other, depending the position of a focused spot of the light focused on the recording surface by the focusing diffraction grating. Therefore, by comparing the intensity of light from one light receiving diffraction grating with that from the other light receiving diffraction grating, there can be seen a positional relationship between the focused spot and the recording surface.