Sony Corporation

Seisuke Yamanaka

Toshimichi Nishimura

Fumio Nagumo

Masatoshi Sase

Shigeyuki Ochi

Makoto Onga

Osamu Yoshioka

Yasuo Kanou

Masaru Shimada

Isao Kajino

Satoshi Shimada

Hiroshi Yamazaki

Tadayoshi Mifune

A solid state image pick-up device comprises a matrix of first and second photo-sensitive elements, vertical shift registers disposed parallel to each other to shift charges from the first and second elements, respective transfer gates between each first and second element and the adjacent vertical shift register, and a horizontal shift register connected to one end of each of the vertical shift registers. An optical shutter is controlled such that the first and second elements are simultaneously exposed to incident light, and a system controller controls the transfer gates and the vertical and horizontal shift registers whereby equal predetermined maximum intervals are available for charging each of the first and second elements, the predetermined intervals being at least two frame periods long, but the starting time for charging for the first and second elements being relatively shifted by a predetermined interval, and reading of the signals from the first and second elements being performed sequentially in a frame period subsequent to closure of the shutter.

Solid state image pick-up devices

A clamp circuit is disclosed, which clamps the black level of output signal of an image pick-up section with an optical black-detecting portion in the horizontal direction provided in an ineffective picture area corresponding to the horizontal blanking interval of the output signal of the section for each horizontal scanning interval. The pulse width at least one clamp pulse immediately after the vertical blanking interval is made greater than that of the other clamp pulses, within the horizontal blanking interval.

Clamp circuit for use in video camera having image pick-up device

A signal processing circuit comprises an image sensor having an optical black level detecting portion, a buffer circuit for receiving an output signal from the image sensor, a clamping circuit for receiving an output from the buffer circuit, and a low-pass filter provided between the buffer circuit and the clamping circuit. This low-pass filter is made operative by a switching circuit in the interval responsive to the black level detecting portion in the output signal of the image sensor, while it is made inoperative in the interval responsive to the image pickup signal detecting portion. According to this circuit, the black level drift can be followed, thereby preventing the appearance of line noise on the screen without being influenced by the sag component due to the AC coupling.

Signal processing circuit including image sensor

A solid state imaging device comprising a charged coupled device CCD for use in a camera which has a shutter and wherein the output of the charged coupled device is supplied to a video processing unit which drives a magnetic recorder for recording images on a magnetic medium and wherein first and second field images are simultaneously picked up by the photosensitive regions of the solid state image sensor when the shutter is opened and the first and second field signal charges are read out sequentially from the charge couple device when the shutter is closed. The invention also provides for sweeping unrequired charges from prior images from the charge coupled device so as to prevent blooming. The exposure on the charge coupled device automatically controls the time or aperture of the exposure system based on detected signals. The shutter is closed for two field periods while the first and second fields are read out so as to prevent smearing and mixing.

Solid state image pickup device

A plurality of sampled signals that differ in phase by 2.pi./N (where N is an integer greater than 1) from one another are mixed by sequentially supplying the sampled signals to a holding circuit, the holding circuit output is buffered in a buffer amplifier to produce the system output having a beneficial high-frequency characteristic. Deterioration of the frequency characteristic of the synthesized output signal for a high frequency range due to a low-pass filter effect stemming from the zero hold in the sample/hold circuit is prevented by the mixing circuit.

Mixing circuit

A dot sequential color signal which is generated in an image pick-up means, as for example a CCD type image sensor is supplied to a first sampling and hold (S/H) circuit, with the frequency of the sampling pulse used in the first S/H circuit being at a predetermined frequency (FO), and the output of the first S/H circuit is supplied to a second S/H circuit, with the frequency of the sampling pulse used in the second S/H circuit being selected to be N times of the predetermined frequency (NFo), so that the frequency of the sampling noise caused by the sampling operation is relatively high compared with the output signal of the image pick-up means, and thus the cut-off frequency of a low pass filter for eliminating the sampling noise can be selected to be high enough not to attenuate the desired signal.

Sample hold circuit for an image pick-up device

A solid state color television camera provided with a control signal generator for producing control signals having signal levels set to any levels by a level setter as dots sequential control signals synchronized with dots sequential camera output signals and a gain control type amplifier gain-controlled according to the level of dots sequential control signal, the level of the dots sequential camera output signal being adjusted by a gain control type amplifier.

Solid state television camera

A multi-chip type CCD color camera is designed to displace respective chips relative to an object image. The sampling action at respective CCD imager chips yields output signals having base-band components and sideband components partially overlapped with each other. In order to separate two components, frequency converting technique is introduced in the signal processing circuit, wherein these components are interchanged in frequency. It is very easy to cancel out original base-band components from respective CCD chips, because the phases of the base-band components are not influenced by chip displacement. Accordingly, there is no need to adjust precise chip alignment in order to improve the resolution of the CCD color camera.

The present invention relates generally to a signal transmission circuit in which a plurality of sampling circuits are interposed, and is directed more particularly to such a signal transmission circuit suitable for use in the signal processing circuit of a solid state television camera in which a semiconductor device such as a CCD and a BBD (bucket brigade device) is employed.

Signal transmission circuit

A white balance control circuit for an encoded composite color television signal is disclosed in which three primary color signals of green (G), blue (B) and red (R) are matrixed to be mixed color signal components, color difference signals of R-G and B-G are provided from the mixed color signal components, and gain control circuits provided on the signal transmission paths of two primary color signals of R and B are so controlled in their gains that the color difference signals become zero, when the white balance adjustment is done.

White balance control circuit

A solid state color television camera having a solid state image sensing device and an optical color filter. In this case, the color separating characteristics of the color filter is so selected that when a predetermined horizontal scanning line is scanned, from the solid state image sensing device there are obtained a red color signal and a luminance signal of the standard system sequentially and alternately, and from a horizontal scanning line adjacent the above horizontal scanning line there are obtained a blue color signal and luminance signal. Also, as the high band component, which constitutes the above luminance signal, the high band component of a composite video output signal, which includes the primary color signal and luminance signal produced by scanning the above horizontal scanning line, is utilized. Further, by scanning the respective horizontal scanning lines, different color difference output signals obtained at every one horizontal scanning line are made in simultaneity and based upon the color difference output signals and luminance signal there is produced a color video signal of the standard system.

Solid state color television camera

A solid state color camera having an image sensing device which has a plurality of image sensing cells aligned in both the horizontal and vertical directions, an optical filter which produces three primary color separated images on the image sensing device, a circuit which reads out an image signal as to satisfy an interlaced signal reading system of a standard television signal, the image signal being comprised of a luminance signal and a chrominance modulated carrier signal, a circuit which supplies a carrier signal to the reading out circuit, the carrier signal being selected approximately equal to or half of a standard color sub-carrier frequency, and a circuit selecting vertical and horizontal frequencies of a read out image signal.

Solid state color camera

A color camera system is disclosed in which a dot-like signal which appears on a TV screen caused by a processing error is effectively eliminated. A pick up device with a color coding filter derives composite signals containing color components modulated at a frequency f.sub.s where the composite signals are obtained in opposite phase line by line. An adder circuit is provided to mix the composite signals obtained from two adjacent lines. A detector detects the 2nd harmonic of f.sub.s from the mixed composite signals. A dual gate MOSFET is provided to suppress a high frequency region of a luminance signal which is derived from the composite signals in response to the detected 2nd harmonic of f.sub.s.

Color camera system

A solid state color camera having a charge coupled device (CCD) on which the image of an object to be picked up is projected. In the color camera, the frequency of a clock signal, which is supplied to a horizontal shift register of the CCD chip for reading out a stored image signal therein, is so selected that the carrier frequency of a chroma signal, which is read out at the output terminal of the horizontal shift register, coincides with the color sub-carrier frequency (3.58 MH.sub.z) of a standard color television signal (for example, NTSC color television signal), and also the order for reading out image informations stored in image sensing elements of the CCD chip arranged in both the horizontal and vertical directions is so selected so that an output signal can be derived from the horizontal shift register with the same phase as that of the color sub-carrier of the standard color television signal.

A color signal modulating system for a color television camera having two CCD's as image pick-up devices for converting optical images into two color signals at alternate scan lines and into a third color signal at consecutive scan lines. Means are provided for developing two color difference signals, one of which is developed from alternate lines of scan. The color difference signals are used to modulate a carrier signal at alternate lines, and means are provided to derive sequentially modulated first and second color difference signals simultaneously at an output of the signal modulating system.

Growing community of inventors

Mitaka, Japan

Seisuke Yamanaka