JPH0243881A - Color picture image pickup device - Google Patents

Abstract

PURPOSE:To obtain a color picture with high picture quality resulting from excellent resolution and color reproducibility by simple constitution in an excellent way by using an image pickup tube and a solid-state image pickup element in common and utilizing the advantages of both the pickup means. CONSTITUTION:A lens 10 is provided to a light emission side from a pickup object and a pickup light passing therethrough is made incident in a half mirror prism 12. Then the light transparent side is arranged with an image pickup tube 14, a luminance signal of a picture is obtained and the solid-state image pickup element 18 is arranged via an optical low pass filter 16 to the other transparent side, and a color filter is provided to the solid-state image pickup element 18 in a on-chip way to obtain a color signal of the picture. Thus, a color picture with high quality in High vision is obtained in expensively and excellently.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a color image capturing device, and particularly to a color image capturing device suitable for color capturing in high-definition.

[Prior art] As a conventional high-definition color camera, for example,
There is a ball tube type as shown in the figure. In the same figure, lens 1
The light from the imaging target (subject) that has passed through 00 enters the three-color separation prism 102, where it is divided into R (red) and G (green).
, B (blue).

These six lights are transmitted through the image pickup tubes 104, 106, and 106, respectively.
108, where each optical image is formed and photoelectrically converted into an electrical signal. Image pickup tubes 104, 106,
The drowsiness signals output from the camera circuits 108 and 108 are sent to the camera circuit 1.
10, and undergoes signal processing of type/Z here to output predetermined television signals such as the NTSC system, that is, color difference signals R-Y, B-Y, and luminance signal Y, respectively.

On the other hand, a prototype solid-state film device with 1035 (vertical direction) x 1920 (vertical direction) pixels has been manufactured. Incidentally, a camera with approximately 500 (vertical direction) x 700 (vertical direction) pixels has been moved to mass production, and this is a single-chip color camera with color filters installed on-chip.

[Problem to be solved by the invention] In a high-definition color camera as described above,
There are the following problems: Three-tube power type requires a higher performance signal processing circuit than normal one, especially for R, G,
The correction or alignment accuracy for registration deviations, which are geometric deviations and distortions between each B image, is more stringent than that of current television cameras, and high performance is required. Therefore, inexpensive and high-performance high-definition color cameras are not yet available.

Similarly, it is difficult to provide solid-state imaging devices with stable and high performance.

As described above, although the resolution and S/N are good for image pickup tubes, if a three-capacity type is used for color, it is difficult to perform registration, and it is difficult to increase the number of pixels for solid-state image pickup devices.

The present invention has been made in view of the above, and an object of the present invention is to provide a color image pickup device with a simple configuration that can obtain high-quality color images in high-definition at low cost. It is.

[Means for Solving the Problems] The present invention provides an optical means for dividing an optical signal from one image, an image pickup tube disposed on one light transmission side of the optical means to obtain a luminance signal of the image, and an image pickup tube for obtaining a luminance signal of the image. The present invention is characterized in that it includes a solid-state image sensor disposed on the other light-transmitting side of the optical means to obtain color signals of the image.

[Function] According to the present invention, an optical means for splitting an optical signal is provided on the light incident side of the camera. An image pickup tube with good resolution characteristics is arranged on one light transmission side of this optical means, and a luminance signal of an image is obtained by this.

On the other light-transmitting side of the optical means, a single-plate color solid-state imaging satin having good one-color separation characteristics is arranged, thereby obtaining color signals of an image.

[Example] An example of the present invention will be described below with reference to the accompanying drawings. First, the configuration of the embodiment will be described with reference to FIG.

In the same figure, there is a lens l on the side where light from the imaging target enters
The imaging light transmitted through this is made to enter the half mirror prism 12. An image pickup tube 14 is disposed on one light transmission side of the half mirror prism 12, and a solid-state image pickup tube 18 is disposed on the other light transmission side via an optical PF (low pass filter) 16. It is located. This solid-state image sensor 18 is equipped with a color filter.

That is, the incident light is divided into two by the half mirror prism 12, and each is divided into two parts by the image pickup tube 14. The light is made incident on the solid-state imaging pad 18. These ti image tubes14. The output sides of the solid-state image sensor 18 are respectively connected to the input sides of a color camera circuit 20, and the color difference signals R-Y, B-Y and the luminance signal Y are outputted from the color camera circuit 20, respectively. It has become.

Next, while referring to the second UA, the color camera circuit 20
An example of the configuration will be explained. In the figure, the output side of the solid-state image sensor 18 described above is connected to the input side of a one-color separation circuit 22. and.

The output side of this color separation circuit 22 is connected to the input side of a one-color correction circuit 24.

On the other hand, the output side of the above-mentioned image pickup tube 14 is connected to the input side of a luminance component II rectifying circuit 28 via an amplifier 26. In this luminance component adjustment circuit 28.

Color signals R, G, and B are each input from the color correction circuit 24.

Next, the one-color correction circuit 24. The output side of the luminance component adjustment circuit 28 is connected to the input side of a gamma circuit (γ circuit) 30.degree. 32, respectively. and.

The output side of one gamma circuit 30 is connected to the input side of the color difference circuit 34, and the output side of the other gamma circuit 32 is connected to the color difference circuit 34. They are each connected to the input side of the aperture compensation circuit 36.

Among these parts, the color separation circuit 221, the color correction circuit, the gamma circuit 301, and the color difference circuit 34 are parts that obtain a color difference signal from one color signal, and the amplifier 26. Luminance component adjustment circuit 28.
Gamma circuit 32. The aperture compensation circuit 36 is for obtaining a luminance signal.

Next, regarding the operation of the embodiment configured as above,
This will be explained with reference to FIGS. 3 to 5. 3 shows the input signal waveforms of the color camera circuit 20, FIG. 4 shows the spectral characteristics of those input signals, and FIG. 5 shows the frequency gain of the input signals. It is shown.

First, when light from an object to be imaged enters the lens 10, it is divided into two parts by the half-mirror pseudosum 12, and one enters the image pickup tube 14 and the other enters the solid-state image sensor 18.

Then, the image pickup tube 14. Solid 1M1! By element 18,
The incident light is converted into an electrical signal and an image signal is output.

Of these, the image pickup tube 14 outputs a luminance signal as shown in FIG. 3(A), and the solid-state image sensor 18 outputs a color signal as shown in FIG. 3(8). Note that this signal is multiplexed from a plurality of color signals.

Also, looking at the spectral characteristics of these signals, first of all, as shown in Figure 4 (A), the luminance signal includes components from about 400 nm to about 700 nm, and 500 nm and 60 nm.
It has a peak approximately in the middle of 0 nm. Next, regarding one color value, between 400nm and 700nm,
As shown in the figure (B), it has R, G, and H peaks, all of which have the same spectral characteristics as the matrix coefficients of the NTSC system or high-definition.

Furthermore, looking at the frequency gain characteristics of these signals, first of all,
As for the luminance signal, 30 M as shown in Figure 5(A)
-3dB at Hz, and for color signals, R
, G, and B are both 5MH as shown by the arrows in the same figure (B).
It is -3 dB above z. Note that the color signal band is horizontal, ! It is assumed that the IF direct ratio is equal to or higher than l/8 (NT
An inexpensive SC system has a brightness of 5 MH
z, the color signal is about 0°5 MHz).

The luminance signal and color signal having the above-mentioned spectral characteristics and frequency characteristics are both input to the color camera circuit 20. Among these, the color signals are first separated into R, G, and B by the one-color separation circuit 22.
or is output to the color correction circuit 24. Then, color correction signal processing is performed here, and the corrected color signals R, G, and B are sent to the gamma circuit 30. Each is output to the luminance component adjustment circuit 28.

On the other hand, after the luminance signal is amplified by the amplifier 26,
The 14 degree component is input to the W adjustment circuit 28. Here, the color signals R, G, and B are used to adjust their components. The adjusted signal is output to the gamma circuit 32.

Next, gamma correction is performed in each of the gamma circuits 30 and 32, and the signals after correction are converted into one color difference circuit 34. Each is input to an aperture compensation circuit 36. Then, signal processing such as band improvement is performed for each color difference signal R-Y, B-Y
, luminance signal Y are output.

According to this embodiment, as described below, since the luminance signal is obtained by the image pickup tube, a signal with a good S/N ratio in resolution characteristics can be obtained. For this reason.

The above-mentioned problem of misregistration does not occur.

Furthermore, since the color signals are obtained using a solid-state image sensor, it is possible to obtain each of R, G, and B color signals with good single-color separation characteristics.

Furthermore, since the structure is simple, it is possible to achieve a reduction in size and weight compared to the conventional three-tube system.

Note that the present invention is not limited to the above-mentioned embodiments, and various design changes are possible.

For example, in the embodiment L, the image pickup tube 14 and the solid-state image sensor 18 are driven simultaneously as shown in FIG. 3, or they may be driven alternately as shown in FIG. If the driving frequency and driving period of the imaging means of lIi number are changed in this way, it becomes impossible to avoid the mixing of noise. In this case, is it necessary to perform time conversion on the color signal? This should be performed after correction processing by the gamma circuit 30.

[Effects of the Invention] As explained above, according to the present invention, an image pickup tube and a solid-state image pickup device are used in combination, and the characteristics of each of the 11 stages of imaging are utilized, resulting in excellent resolution and 9 color reproducibility. This has the advantage that high-quality color images can be obtained with a simple configuration.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing an example of the configuration of an embodiment of the present invention, FIG. 2 is a circuit block diagram showing an example of the configuration of a color camera circuit according to this embodiment, and FIG. 4 is a line diagram showing the spectral characteristics of the outputs of those imaging means, 5th [;/I is a line diagram showing the frequency characteristics of the outputs of those imaging means, and FIG. 6 is a diagram showing the frequency characteristics of the outputs of those imaging means. FIG. 7 is a diagram showing an example of the output waveform of the imaging means when other driving is performed in this embodiment. This is a configuration 1 showing an example of the device. 12... Half mirror prism, 14... Image pickup tube,
18... Solid-state tM image element, 20... Color camera circuit. Patent Applicant Kunio Kakiki, Representative of Jiki Victor Co., Ltd. (A) (B) Procedural Amendment to the Onryo Diagram (Voluntary) 1989 1st October 3rd

Claims (1)

[Claims] In a color image capturing device that obtains a luminance signal and a color signal of an image using a plurality of image capturing means, there is provided an optical means for dividing a light signal from the image, and an optical means disposed on one light transmission side of the optical means for splitting the light signal from the image. an image pickup tube that obtains a luminance signal of an image;
A color image pickup device comprising: a solid-state image pickup device disposed on the other light transmission side of the optical means to obtain color signals of the image.