JPH0514910A - Optical block for multi-plate type color camera - Google Patents

Abstract

PURPOSE:To shorten a wiring between the terminal of a solid-state image pickup element and a side circuit and also to improve S/N at the time of arranging a driving system on the side of a color separating prism. CONSTITUTION:Plural pads 9L and 9R provided on CCD chips 6R, 6G and 6B are arrayed at both side faces of the color separating prism 10 so that the wiring with a CCD drive circuit 7 arranged on the side of the color separating prism 10 is shortened.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an optical block for a multi-plate color camera.

[0002]

2. Description of the Related Art FIG. 5 shows various structural examples of an optical block for a multi-plate color camera. In the figure, (A) shows one example of a three-plate type optical block, and (B) to (D) show three examples of a two-plate type optical block.

The color separation prism 10a in the three-plate type optical block (A) is composed of three prisms bonded together. The first prism reflects blue (B) and transmits red (R) and green (G). The second prism reflects red and transmits green, and the third prism transmits green. Then, three solid-state imaging devices 9R, 9G, 9B are arranged on the emission surface side of each divided light.

The color separation prisms 10b to 10d in the two-plate type optical blocks (B) to (D) are formed by laminating two prisms. Then, in the example of FIG. (B), the first prism reflects green, the red and blue are transmitted, the second prism transmits red and blue as they are, and two solid-state image pickup devices 9G are provided on each emission surface side. , 9R / B are arranged respectively.

In both the examples of FIGS. (C) and (D), the first
The prism reflects the chroma (C) component (R / G / B) and transmits the luminance (Y) component, and the second prism transmits the luminance (Y) component as it is. The image pickup devices 9C and 9Y are arranged respectively.

However, in the case of the example of FIG. 6C, since the chroma component is reflected and emitted again in the first prism, it is incident on the solid-state image pickup device as a normal image, whereas in the example of FIG. In the case of (3), since the chroma component is directly emitted, it is incident on the solid-state image sensor 9C as a mirror image.

[0007]

By the way, in the conventional solid-state imaging device, as shown in FIG. 6, pads 9U and 9D are arranged above and below the imaging region 14 on the device chip, and the device chip is incorporated. Since the pins (terminals) are arranged on the top and bottom of the package as well, the pins arranged on the top and bottom of the package hinder the miniaturization of the color separation prism in response to the demand for smaller color cameras and higher image quality. There was a drawback that

Further, when the drive system is arranged on the side surface of the color separation prism, the distance from the upper and lower pins of the package to the side surface of the prism becomes long, and this long wiring acts as an antenna, so the vertical transfer clock , Horizontal transfer clock, etc. jump into the output section as noise, causing S / N
There is also a problem that it is easy to cause deterioration of

The present invention has been made in view of the above-mentioned points, and when the drive system is arranged on the side surface of the color separation prism, the wiring between the terminal of the solid-state image pickup device and the side surface circuit is shortened and It is an object of the present invention to provide an optical block for a multi-plate color camera, which can improve the S / N.

[0010]

An optical block for a multi-plate color camera according to the present invention is arranged on a color separation prism for splitting an incident light into a plurality of primary color lights, and an exit surface side of the split light of the color separation prism. A plurality of solid-state image pickup devices and a drive circuit for a plurality of solid-state image pickup devices arranged on the side surface of the color separation prism. It is arranged on both sides.

[0011]

In the optical block for a multi-plate color camera according to the present invention, by arranging a plurality of terminals provided on the solid-state image pickup device on both side surfaces of the color separation prism,
The S / N can be improved by shortening the wiring to the circuit arranged on the side surface of the prism and eliminating the influence of noise as the wiring is shortened.

[0012]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 is a schematic perspective view showing an embodiment of a three-plate type optical block according to the present invention. In the figure, a color separation prism 10 for separating incident light into three primary color lights
2 is formed by laminating three blocks of the first to third prisms 1 to 3, and the dichroic layers 4 and 5 made of a non-metal material are provided at the boundary portions of the prisms. The visible light is selectively reflected by the interference of light and the rest is passed.

In the color separation prism 10, the first prism 1 reflects blue, the red / green is transmitted, the second prism 2 reflects red, the green is transmitted, and the third prism 3 transmits green. Thus, the incident light is split into light of three primary colors. Then, for example, CCD chips 6R, 6G, and 6B, which are solid-state image pickup devices, are directly attached to the emission surface of each divided light. A known optical adhesive that does not absorb light can be used to attach the CCD chips 6R, 6G, and 6B to the color separation prism 10.

A so-called interline transfer CCD solid-state image pickup device will be described with reference to FIG. In the figure, a plurality of photosensors 11 that are two-dimensionally arranged in a pixel unit and perform photoelectric conversion, and signal charges that are arranged in each vertical column of these photosensors 11 and that are read out through a read gate 12 are arranged in a vertical direction. An image pickup area 14 is configured by the vertical transfer register 13 that transfers the image data to the image pickup area 14. The vertical transfer register 13 uses the vertical transfer clock φ _V1 ~
4 phase drive by φ _V4 .

The signal charges transferred to the vertical transfer register 13 are sequentially transferred to the horizontal transfer register 15 in units corresponding to one scanning line. The horizontal transfer register 15 is driven in two phases by the horizontal transfer clocks φ _H1 and φ _H2 . The signal charges for one scanning line transferred to the horizontal transfer register 15 are sequentially transferred in the horizontal direction and supplied to the floating diffusion (FD) 16 which is an output unit.

A source follower amplifier 17 for detecting signal charge is connected to the floating diffusion 16. The source follower amplifier 17 detects the signal charge transferred to the floating diffusion 16 and converts it into an electric signal for use in a television. It is derived as a John signal. The source follower amplifier 17 has a two-stage configuration, for example.

The CCD solid-state image pickup device having such a structure is a CC
It is driven by the D drive circuit 7. That is, CC
The D drive circuit 7 includes a four-phase vertical transfer clocks φ _{V1 to} φ _{V4 for} the vertical transfer unit, two-phase horizontal transfer clocks φ _H1 , φ _{H2 for} the horizontal transfer unit, a reset gate pulse φ _{RG for the} output unit, and a reset drain voltage. V _RD and various power supply voltages V _DD , V _GG , V
Drive control is performed by supplying _SS , GND, etc.

The CCD drive circuit 7 is unique to each of the CCD chips 6R, 6G, and 6B. As shown in FIG. 1, the CCD drive circuit 7 is integrated into an IC and mounted on a printed circuit board 8 on the side surface of the color separation prism 10. It is attached. And C
Each pin (terminal) of the CD drive circuit 7 is electrically connected to each pad of the CCD chips 6R, 6G, and 6B having the above-described configuration, for example, by wire bonding.

The electrical connection does not necessarily have to be made by wire bonding, but can be made by bending a flexible substrate, for example. Further, the CCD drive circuit 7 is connected to the color separation prism 1.
Although it is attached to the side surface of No. 0, it may be attached to a support plate (not shown) of the prism.

By the way, CCD chips 6R, 6G, 6B
In each case of the interline transfer type CCD, the minimum required number of pads (terminals) is φ _{V1 to} φ _V4 (for 4-phase drive) for the vertical transfer section.
Φ _H1 , φ _H2 (for 2-phase drive)
And for the three output unit for _{φ RG, V DD, V GG} , V SS, 4 pieces for V _out as other, V _sub (a voltage applied to the substrate), V
_L (voltage applied to the protection transistor provided in each pin for electrostatic withstand voltage) and three groups for GND (total number of pads: 14).

The 14 pads are the CCD chip 6
As shown in FIGS. 1 and 4, the R, 6G, and 6B are divided into two groups and arranged in a row on both side surfaces of the color separation prism 10. These pads 9L, 9R
For example, two specific examples of the grouping will be described below.

In the first embodiment, the horizontal transfer clock system of φ _H1 , φ _H2 , and φ _RG and V _DD , V _GG , V _SS , and V are shown as columns of pads 9L _{1 to} 9L _m on the left side in FIG. seven pads of the output system of the _out, as a column of the right pad _{9R 1 ~9R n, φ V1 ~φ} V4 of the vertical transfer clock system and V _sub, V _L, other GND seven pads, respectively Shall be arranged.

As described above, since the horizontal transfer clock system is mainly arranged as the left pad row and the vertical transfer clock system is mainly arranged as the right pad row, seven pad rows are provided on the left and right sides. The pad arrangement has good symmetry, which is particularly advantageous for downsizing the optical block.

On the other hand, in the second specific example, the pad 9 on the left side is
As columns of L _{1 to} 9L _m , V _L , GND and V _DD ,
6 pads of DC / output system of V _GG , V _SS and V _out
Horizontal transfer clock systems φ _H1 , φ _H2 , φ _RG , and vertical transfer clock systems φ _{V1 to} φ are arranged as columns of pads 9R _{1 to} 9R _n on the right side.
Eight pads of the clock system of _V4 and _Vsub are arranged respectively.

As described above, by arranging the DC / output system pad row and the clock system pad row separately, it is possible to eliminate the influence of noise and the like from the clock system to the DC / output system. Therefore, CC with excellent electrical characteristics
It is possible to obtain an optical block including the D solid-state image sensor.

The present invention is not limited to CCD solid-state image pickup devices, but can be applied to MOS-type and amplification-type solid-state image pickup devices in general. In addition, in the above-described embodiment, the case where the invention is applied to the three-plate type optical block has been described.
The same can be applied to the two-plate type optical block as shown in (B) to (D).

Further, in the above embodiment, the arrangement of the pads in the case where the CCD chips 6R, 6G and 6B are not incorporated in the package and directly attached to the split light emission surface of the color separation prism 10 has been described. However, it can be similarly applied to the pin arrangement in the case where the CCD chips 6R, 6G, and 6B are incorporated in the package and arranged on the side of the split light emission surface of the color separation prism 10.

[0028]

As described above, according to the present invention,
By arranging multiple terminals provided on the solid-state image sensor on both sides of the color separation prism, the wiring to the side circuit of the prism can be shortened, and the noise caused by shortening the wiring. The effect of being able to improve S / N by eliminating is.

Further, the pad row of the horizontal transfer clock system is mainly arranged on one side of both side surfaces of the color separation prism, and
By arranging the pad row of the vertical transfer clock system mainly on the other side, the symmetry of the pad arrangement is improved, which is particularly useful for downsizing the optical block.

Furthermore, by separating the DC / output system pad row and the clock system pad row and arranging them on both sides of the color separation prism, respectively
Since the influence on the output system can be eliminated, it is possible to obtain an optical block including a solid-state image pickup element having excellent electrical characteristics.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing an embodiment of a three-plate type optical block according to the present invention.

FIG. 2 is a configuration diagram of a three-color separation prism.

FIG. 3 is a configuration diagram showing an example of an interline transfer type CCD solid-state imaging device.

FIG. 4 is a front view showing an array of pads of a CCD chip according to the present invention.

FIG. 5 is a configuration diagram showing various examples of an optical block for a multi-plate color camera.

FIG. 6 is a front view showing an arrangement of pads of a conventional CCD chip.

[Explanation of symbols]

4,5 dichroic layer 6R, 6G, 6B CCD chip 7 CCD drive circuit 9L, 9R, 9U, 9D pads 10 color separation prism 11 Photo sensor 13 Vertical transfer register 14 Imaging area 15 Horizontal transfer register 16 Floating diffusion 17 Source Follower Amplifier

Claims (3)

[Claims] 1. A color separation prism for splitting incident light into a plurality of primary color lights, a plurality of solid-state image pickup elements arranged on the split light emission surface side of the color separation prism, and a side surface side of the color separation prism. And a drive circuit for driving the plurality of solid-state image pickup devices, wherein a plurality of terminals in each of the plurality of solid-state image pickup devices are arranged on both side surfaces of the color separation prism. Optical block for plate color camera. 2. Of the plurality of terminals in each of the plurality of solid-state image pickup devices, a vertical transfer clock system terminal is on one side surface side of the color separation prism and a horizontal transfer clock system terminal is on the other side surface side. The optical block for a multi-plate color camera according to claim 1, wherein the optical blocks are arranged on the respective sides. 3. Of the plurality of terminals in each of the plurality of solid-state imaging devices, the DC and output system terminals are on one side surface side of the color separation prism and the clock system terminals are on the other side surface side. Claim 1 characterized by each being arranged.
An optical block for the described multi-plate color camera.