Abstract: To improve the quality of the demodulated signal without altering the form in which an AM radio wave is transmitted, the received amplitude-modulated signal is converted to a single-sideband signal, and the information signal demodulated from the phase term of this converted single-sideband signal.

Abstract: To improve the quality of the demodulated signal without altering the form in which an AM radio wave is transmitted, the received amplitude-modulated signal is converted to a single-sideband signal, and the information signal demodulated from the phase term of this converted single-sideband signal.

Abstract: The invention addresses itself to the task of providing a medium-frequency stereo broadcast receiving circuit that does not require any alteration of the radio wave format used in the medium-frequency stereo broadcast system that has become the de facto standard, and that receives transmitted broadcast waves and removes, in the course of the demodulation process, disturbance that has affected the signal during its propagation, thereby improving the audio quality of the demodulated signal and obtaining the full potential of the stereo effect. To achieve this, the received medium-frequency stereo broadcast wave is converted to a single-sideband signal, and the sum signal (L+R) is demodulated from the phase term of this converted single-sideband signal. The difference signal (L−R) is demodulated from the phase term of the received medium-frequency stereo broadcast wave and from the demodulated sum signal output.

Abstract: This invention addresses itself to the task of securing excellent narrowband transmission quality when transmitting audio signals such as voice and music, or various kinds of multimedia signal, by means of unidirectional or broadcast communication systems. Excellent demodulation characteristics are obtained by reducing the required transmission bandwidth by using SSB modulation technology, and by performing RZ SSB demodulation at the receiving side. The sideband and the carrier component are transmitted at a sufficient distance from one another in the frequency domain so that even if frequency stability in the transmitting and receiving circuits is not very high, there is little likelihood of quality deterioration due to frequency instability, and so that the receiving circuit is easier to implement, since less sharply selective bandpass filters are required.

Abstract: An apparatus for picking-up an optical image of object including a lens system for forming the optical image of object, an optical filter for suppressing moire fringes, a color separation system for separating the optical image into green, red and blue color images, and three solid state image sensors for receiving the green, red and blue color images, respectively. The optical filter having a first quartz plate for separating ordinary and extraordinary light rays from each other in a direction of +45.degree. with respect to the horizontal direction, a second quartz plate for separating ordinary and extraordinary light rays from each other in the horizontal scanning direction, and a third quartz plate for separating ordinary and extraordinary light rays from each other in a direction of -45.degree. with respect to the horizontal scanning direction. The optical filter has two trap points, one at a sampling frequency f.sub.s and the other near 1.5f.sub.

Abstract: A solid state image sensor comprises a CCD type image sensing device and a signal detector. This signal detector comprises an FDA type signal detection circuit connected to a signal pick-up terminal of the image sensing device and having a small amount of saturating signals and low noise, an FDA type signal detection circuit connected to the signal pick-up terminal and having a large amount of saturating signals and high noise, and a signal composing circuit for composing the outputs of both signal detection circuits and outputting a composed output and changing a composing ratio in accordance with the output of the FDA type signal detection circuit.

Abstract: An optical low pass filter for use in an imaging device including an objective lens and a solid state image sensor forming a plurality of picture elements thereon, which filter comprises a diffraction grating disposed between the objective lens and the solid state image sensor. The diffraction grating is of a type which the periodicity of an image of the diffraction grating projected onto the solid state image sensor by the objective lens is selected to be twice or 1/n of the periodicity of the picture element, wherein n represents an integer.

Abstract: A solid state image sensing device comprises a great number of light receiving elements arrayed in rows and columns, a plurality of vertical CCD registers respectively coupled to columns of the light receiving elements for vertically transferring signal charges sensed by the light receiving elements, a horizontal CCD register for horizontally transferring the signal charges transferred from the vertical CCD register, an adder section for adding together signal charges obtained from a predetermined number of light receiving elements arrayed in columns and rows to form one added signal charge and for obtaining a plurality of added signal charges for all the light receiving elements in each of fields, and a field switcher for introducing signal charges obtained from an array of light receiving elements with at least one element shifted from the previous field to the adder section in each field.

Abstract: An information recording medium comprises a silicon substrate, a silicon dioxide film formed on one principal surface of the semiconductor substrate and a silicon nitride film formed on the silicon dioxide film. A recording electrode stylus is moved relative to and along the surface of the silicon nitride film while applying a recording signal voltage between the stylus and substrate, thus causing charges corresponding to the recording signal voltage to be passed through the silicon dioxide film by the tunnel effect and stored in the silicon nitride film.