JPS61264873A - Solid-state image pickup device - Google Patents

Abstract

PURPOSE:To obtain double resolution equivalently without the reduction of sensitivity by arranging a triangular prism at a photodetecting plane side, oscillating a mask sheet having an aperture hole at the photodetecting plane side and making incident different rays of light on the same picture element alternately. CONSTITUTION:At the photodetecting plane of a solid-state image pickup element 1, a picture element 1a is regularly arranged. At a mask sheet 2, a slit having 1/2 width of a picture element pitch D is formed with the picture element pitch D. As for a prism 3, the section of which is shaped as triangular and the mountain of which is faced with an incident light side and the pitch of the mountain is set as the picture element pitch D. With oscillating the mask sheet 2 with amplitude of 1/2D crosswise, and when it is moved in arrow (h) direction, rays of light that pass through on one side of inclined surfaces of the prism 3 are shaded and when it is moved in arrow h' direction, the rays of light that pass through on the other side of the inclined surfaces can be shaded. When accumulated data corresponding to one horizontal directioned row in the picture element 1a are scanned with a horizontal scanning signal and are outputted to outside and a slit sheet is moved at a high speed at every vertical scanning and one frame data is generated with synthesizing each data, the number of a picture element in the horizontal scanning direction is equivalent to be doubled.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a solid-state imaging device in which the resolution of a solid-state imaging device is improved without decreasing or reducing sensitivity.

[Prior art]

This type of solid-state imaging device includes one in which the arrangement of adjacent pixels (photosensitive units) of the solid-state imaging device is shifted by two pixel pitch to create a staggered pattern to increase the number of pixels, and one in which the number of pixels is increased by shifting the arrangement of adjacent pixels (photosensitive units) of the solid-state imaging device by two pixel pitches. It has already been proposed to vibrate by a two-pixel pitch using a piezoelectric element or the like.

However, although the former can be realized for MOS type devices in which vertical transfer lines can be realized with aluminum wiring,
It is difficult to apply to a CCD type device, and signal processing is also complicated.

On the other hand, the latter vibrates the relatively heavy element itself, making it difficult to control and posing problems in terms of reliability.

[Purpose of the invention]

The present invention has been made in view of the above points, and its purpose is to obtain a resolution that is equivalently twice the resolution determined by the number of pixels of a solid-state image sensor, and at the same time, it does not involve a decrease in sensitivity. First, it is an object of the present invention to provide a solid-state imaging device which does not require vibration of the device and which requires a simple pixel arrangement of the solid-state imaging device.

[Structure of the invention]

For this purpose, the solid-state imaging device of the present invention has a mask plate having an opening hole arranged substantially parallel to the light-receiving surface side of the solid-state image sensor, and has a substantially triangular cross section so that one side is substantially parallel to the light-receiving surface side. By arranging a prism and vibrating the mask plate, different light beams passing between each of the two adjacent slopes of the prism and the one side are alternately selected, so that the same light beam of the solid-state image sensor is It is configured so that the light is incident on the pixels of .

〔Example〕

Examples of the present invention will be described below. The figure shows one example thereof. In the solid-state imaging device of this embodiment, a mask plate 2 as shown in FIG. 2 is arranged parallel to the light-receiving surface side of a two-dimensional solid-state imaging device (MO3 type or CCD type) 1 as shown in FIG. Furthermore, a prism 3 is arranged on the upper surface of the mask plate 2.

The light receiving surface of the solid-state image sensor 1 has vertical and horizontal directions.
Pixels (photosensitive unit portions) la are regularly arranged. d is the pixel width, and D is the pixel pitch. The mask plate 2 has a width that is 1/2 of the pixel pitch D, and has a length that is the same as or slightly longer than the length of the vertical row of pixels 1a! The slits 2a are formed in parallel at a pixel pitch D. The prism 3 has a triangular cross section, one side of which is parallel to the light-receiving surface (pixel formation surface) of the solid-state image sensor 1, the peaks of which face the light incident side, and the pitch of the peaks is the pixel pitch D. is arranged so as to coincide with the pixel 1a of the solid-state image sensor l.

Therefore, if the mask plate 2 is vibrated in the horizontal (horizontal) direction (arrow h, h' direction) with an amplitude V2D, as shown in FIG. 3(a), (
As shown in b), when moving in the direction of the arrow, the light passing through one slope of the mountain of the prism 3 is blocked, and when moving in the direction of the arrow h', the light passing through the other slope of the same mountain of the prism 3 is blocked. The light passing through can be blocked. In this case, unblocked light is incident on the same pixel.

Therefore, the horizontal (H) direction of the pixel 1a of the solid-state image sensor 1 -
The accumulated data corresponding to the columns is scanned with a horizontal scanning signal and transferred to the outside, and after this is done for each column, the slit plate 2 is moved in the direction of the arrow at every timing of vertical scanning, which returns to the beginning again, that is, every vertical scanning. Alternatively, the image data obtained by moving in the h' direction at high speed, for example, the image data obtained while moving in the direction indicated by the arrow, is defined as A field data, and the image data obtained while moving in the direction indicated by the arrow h' is defined as B field data, and both fields are If the data is combined into one frame data, the fourth
As shown in the figure, this is equivalent to doubling the number of pixels in the horizontal scanning direction, and the resolution improves. lal and laz are equivalent pixels corresponding to pixel 1a.

In addition, here, % of the area of the pixel 1a is covered by the mask plate 2, but since the light bent by the prism 3 enters the entire surface of the pixel 1a, no matter which direction the mask plate 2 moves, , the entire surface of the pixel 1a works effectively, and the sensitivity does not decrease.

In this regard, when the prism 3 is not used, the resolution is improved as described above, but since the effective portion of the pixel 1a is halved, the amount of light received is reduced and the sensitivity is reduced.

Note that if the light-receiving area of the pixel 1a is small, a prism with a large refractive index in the peripheral portion (the portion of the slope away from the mountain) may be used.

FIG. 5 shows an example in which a prism 3' having an outwardly projecting rounded slope is used for this purpose.

Further, in the above, the mask plate 2 is interposed between the prism 3 (3') and the solid-state image sensor 1, but as shown in FIG.
It is also possible to block the light that enters the area.

FIG. 7 shows a circuit for driving such a solid-state imaging device and extracting image data from it. 4
is the timing generator, from which the horizontal scanning pulse H
p, a vertical scanning pulse Vp, and a data processing synchronization pulse P are output. 5 indicates the solid-state image sensor 1 in the horizontal direction (H);
A clock drive circuit that scans in the vertical direction (V), 6 a delay circuit that delays the horizontal scanning pulse Hp by the alternately shielded portion of the pixel 1a, that is, the pinch of each pixel; 8 is a preamplifier that amplifies the output data from the solid-state image sensor 1; 9 is a process circuit that processes the signal from the preamplifier 8; 10 is a circuit that combines image light into the photosensitive portion of the solid-state image sensor 1; It is a lens that focuses.

In this circuit, if the vertical scanning period is 1760 seconds, the vibration period of the mask plate 2 is twice that, 1/30 second. In this case, 30 frames of images can be read per second. Furthermore, in the above-mentioned A field and B field, the pixel data corresponds to the vertical scanning pulse Vp.
Since the timing is shifted by a time corresponding to a two-pixel pitch, signal processing for subsequent reproduction (recording, etc.) becomes easier.

Although the number of pixels in the horizontal direction is doubled in the above example, if the mask plate 2 and prism 3 are rotated 90 degrees,
It is also possible to double the number of pixels in the vertical direction. Further, the opening of the mask plate 2 is not limited to the slit 2a, but may be a hole that shields only the pixel portion. This increases the strength of the mask plate 2.

〔Effect of the invention〕

As described above, according to the present invention, since light carrying image information is alternately incident on the pixels of the solid-state image sensor, it is possible to equivalently double the number of pixels of the solid-state image sensor without reducing the sensitivity.
The number of pixels can be doubled, and the imaging resolution can be doubled. In addition, the selection of light carrying different image information is done by the vibration of the mask plate, and since the mask plate can be made considerably lighter, the driving mechanism can be simplified compared to the case where the element itself is driven. Increased reliability,
It requires less power, and the pixel arrangement of the solid-state image sensor can be simple.

[Brief explanation of drawings]

Fig. 1 is a plan view of the solid-state image sensor, Fig. 2 is a plan view of the mask plate, and Fig. 3 (a) is a side view of the solid-state image sensor. 4 is a diagram for explaining the increase in the number of pixels, FIG. 5 is an explanatory diagram showing a modified example of the prism, FIG. 6 is an explanatory diagram of another embodiment in which the arrangement position of the mask plate is changed, and FIG. FIG. 7 is a circuit diagram for driving and data retrieval of the solid-state imaging device of this embodiment. DESCRIPTION OF SYMBOLS 1... Solid-state image sensor, 1a... Pixel, 2... Mask plate, 2a... Slit, 3.3'... Prism.

Claims (4)

[Claims] (1) A mask plate having an opening hole is arranged substantially parallel to the light-receiving surface side of the solid-state image sensor, and a prism having a substantially triangular cross section is arranged so that one side is substantially parallel to the light-receiving surface side, and the above-mentioned By vibrating the mask plate, different lights passing between each of the two adjacent slopes of the prism and the one side are alternately selected and incident on the same pixel of the solid-state image sensor. A solid-state imaging device characterized by: (2) The solid-state imaging device according to claim 1, wherein the mask plate is disposed between the solid-state imaging device and the prism. (3) The solid-state imaging device according to claim 1, wherein the prism is disposed between the solid-state imaging device and the mask plate. (4) The solid-state imaging device according to claim 1, wherein the opening hole of the mask plate has a width approximately half the pitch of the pixels.