DE4006599A1 - IMAGING SOLID COMPONENT AND ELECTRONIC SINGLE IMAGE CAMERA USING THIS - Google Patents

Abstract

In an interline CCD imaging device suitable for use in a still camera, the vertical transfer portions 14, which serve to take accumulated electrical charges corresponding to the quantity of light received photosensors 12 and transfer them to an output horizontal transfer region 16 one line at a time, are provided with transparent electrodes and are themselves photosensitive. Either the photosensors or the transfer portions are provided with sets of three colour filters, whereby luminance and colour signals can be obtained sequentially once the camera shutter has closed, the first obtained signal being stored for combination with the second signal. The arrangement provides increased horizontal resolution and an efficient use of incident light. <IMAGE>

Description

The present invention relates to an imaging Solid state device, in which a color signal and a Luminance signal used to form a color image needed to be generated at the same time, and one electronic still camera in which such solid-state imaging device is used to reproduce a high resolution color image.

Various electronic still cameras (single image video cameras) have been developed recently been in which an imaging component to Umwan object mapping into electrical signals and a magnetic disk (video floppy) for recording the electrical signals used to be in place of a conventional silver salt film a single image or Record single images.

Fig. 6 shows an IL-CCD (CCD of the interline type), which is one of the known imaging components, which are used in an electronic single image camera. In an arrangement shown in Fig. 6, a plurality of rows are made of photosensitive parts 101 , each row consisting of a large number of picture elements (photodiodes) 103 , which are continuously arranged vertically, and a plurality of rows of vertical transfer parts ( Vertical transfer CCD's) 105 alternately or alternately arranged side by side. The electric charges accumulated in the image members 103 are transferred to the associated vertical transfer parts 105 at a time or at a time, so that the electric charges transferred to the vertical transfer parts 105 in the vertical direction are gradually transferred to a horizontal transfer part (not shown) or transferred. Thereby, each line of the electric lines transmitted to the horizontal transfer parts can be read from the horizontal transfer part.

The light-sensitive parts 101 are provided on their light-sensitive surfaces (light-receiving surfaces or light-receiving surfaces of the picture elements 103 ) with complementary color filters, through which only yellow light (Ye), cyan light (Cy) and magenta light (Mg) can be transmitted, as in Fig. 7 shown, or provided with primary color filters through which only red light ( R ), green light ( G ) and blue light ( B ) can be transmitted, as shown in Fig. 8. The color signals for forming a color image are obtained by the electrical charges accumulated in the picture elements 103 , which receive light through the color filters.

The vertical transfer parts 105 are provided on their light-capturing surfaces with light-intercepting or cutting layers, so that only the electrical charges transmitted by the light-sensitive parts 101 can be accumulated.

Compared to a conventional silver salt picture an electronic still camera that give an image of the solid state component of the type mentioned above  det, but poor or poor image quality. In particular, the resolution of the electronic single image camera, which is an imaging solid-state component used is not comparable to that of silver salt image.

To increase the resolution, it is necessary to Density of the image elements of solid-state imaging element to increase or separate imaging components elements for signal components made of red light, green Light and blue light (so-called three-tube camera) to provide.

The provision of a variety of imaging solids components naturally leads to a complex one and expensive camera.

On the other hand, there are limitations in modern technology tongues regarding an increase in the density of the image elements ment and accordingly it is very difficult or almost impossible an inexpensive electronic single Realize image camera with high resolution.

A first object of the present invention is in creating an imaging solid state device with which a high quality image with high resolution through a single imaging device can be formed can, and to create an electronic still camera fen, which is such a single imaging solid perbauelement used.

The inventors of the present invention aimed at one photoelectric conversion function and an electri cal charge accumulation function of the vertical transfer parts of the imaging solid-state component.  

To solve the above-mentioned problem, according to the present invention an imaging solid state created element that includes: photosensitive parts, the electric charges accumulate that of them received amount of light correspond, and vertical transfer parts that accumulate electric charge, the the amount of light received from them correspond ren, whereby the vertical transfer parts that of the light sensitive parts accumulated electrical charges transfer, and taking the photosensitive parts and the vertical transfer parts alternate in horizonta ler direction are arranged, the vertical trans parts have light-receiving surfaces on which are transparent electrodes, and color filters of the three Have primary colors that the three primary colors read through and alternating in a predetermined series order or order are arranged.

Because with this arrangement the vertical transfer parts on where the color filters are provided, the electrical Accumulate charges corresponding to the amount of light that falls through the color filters on them can be a color signal obtained by the vertical transfer parts. On the other hand, since the photosensitive parts the elec accumulate charges that amount to the amount they correspond to falling light, a luminance signal received from the photosensitive parts the.

As can be seen from the foregoing, according to the present invention the vertical transfer parts, which were only used in the prior art to the in the light-sensitive parts accumulated electrical To transfer charges, also as photosensitive Parts used, resulting in increased use effi ciency of the striking light and an increased hori  zonal resolution leads.

Alternatively, it is possible to color the primary colors on the photosensitive parts in a pre agreed to provide alternating order. At In this alternative, the transparent electrodes are on each of the light receiving surfaces of the vertical Transfer parts are provided to shine light through to transmit them so that the color signal and the Lumi nance signal by the photosensitive parts or Vertical transfer parts can be obtained. As a result, you can both the color and luminance signals from one single imaging solid-state device with high Density can be obtained.

According to another aspect of the present invention an electronic still camera is created which comprises: an imaging solid-state component, such as previously constructed or described, a latch device for storing the color signal data or the from the vertical transfer parts of the imaging festival body component generated luminance signal data, and an imaging signal shaping device for forming an object image signal in accordance with the Luminance signal or the color signal which of the photosensitive parts is formed, and the color signals or the luminance signal, which in the signal storage device are stored and with the Luminance signal or the color signal are synchronized, which is formed by the photosensitive parts.

With this arrangement, the color signal and the Lu Minance signal independent of a single imaging Solid state device can be obtained, so that an Ob ject image with high resolution generated inexpensively can be.  

With an electronic still camera according to the present invention will continue to be the over the Color filters accumulated electrical charges as In formation for a color signal to form an object education used and not through the color filter accumulated electrical charges are called informa tion for a luminance signal to form an object image education used in the individual imaging the solid state device, and accordingly both Color signal as well as the luminance signal from a single NEN imaging solid-state device high density will hold.

The invention will now be described in detail with reference to FIG the attached drawing describes:

Fig. 1A and 1B are different schematic top views of an imaging solid state device in accordance with one aspect of the present invention;

Fig. 2 is a cross sectional view taken along the line II-II in Fig. 1A;

Fig. 3 is a block diagram of a control system of a single electronic camera in which an imaging solid body component shown in Fig. 1 is installed;

Fig. 4 is a flow diagram of a control system of Fig. 3;

Fig. 5 is a diagram showing a timing relationship of a control system shown in Fig. 3;

Fig. 6 is a schematic view showing a structure of a known imaging solid component; and

FIGS. 7 and 8 are schematic views showing the color filter used in a known image forming solid state device shown in Fig. 6.

The following description is of preferred fiction according embodiments of an imaging solid component and an electronic still camera directed such an imaging solid component used.

Fig. 1A showing a construction or a construction of a solid-state imaging device 10 according to an aspect and an embodiment of the present invention.

The basic structure of the photosensitive part of the solid state imaging device 10 shown in Fig. 1 is similar to that of a conventional inter-row type solid state imaging device.

The imaging solid-state component 10 namely has light-sensitive parts 12 with photodiodes (image elements) 13 , which accumulate the electrical charges corresponding to the amount of light striking them, vertical transfer parts 14 , into which the electrical charges accumulated by the photodiodes 13 at a time or are transferred at once to transfer the electric charges successively, and a horizontal transfer part 16 that reads each line of electrical charges transferred from the vertical transfer parts 14 .

It should be noted that the photosensitive parts 12 , the vertical transfer parts 14 and the horizontal transfer 16 are formed on the same integrated circuit board or on the same integrated circuit.

The photosensitive parts 12 and the vertical transfer parts 14 are arranged alternately side by side in the vertical direction. Each row of photosensitive parts 12 has a large number of photodiodes 13 which are arranged independently in the vertical direction in high density.

The light-receiving surfaces (light-sensitive surfaces) of the vertical transfer parts 14 have a pair of transparent electrodes Φ V from e.g. Polysilicon or the like, through which almost all (almost 100%) visible light can be transmitted. The transparent electrodes Φ V are arranged to correspond to the assigned photodiodes 13 of the assigned vertical parts 12 on one side thereof.

In the illustrated embodiment, which is applied to a four-phase drive or operation, each pair consists of four transparent electrons Φ V 1 ∼ Φ V 4 , so that a plurality of pairs of electrodes are arranged in succession.

The transparent electrodes Φ V are provided on their surfaces with stripe filters, which have the primary color filters 18 R , 18 G and 18 B for the three primary colors red ( R ), green ( G ) and blue ( B ), which are consecutive in vertical Direction and are arranged in the horizontal Rich direction in order to correspond to the vertical transfer parts 14 or to correspond with them. When recording on the floppy disk or magnetic disk, the recording tape of the color signal carries a maximum of about 1 MHz. This is the reason that the stripe filters are used. Color filters arranged in a mosaic arrangement can be used, but they have a deteriorated S / N ratio and a lower color reproducibility of the color signal.

An object image is formed on the surface (light-capturing surface) of the imaging solid-state component 10 by a photographic lens.

In the solid-state imaging element 10 constructed as above, the electrical charges corresponding to the intensity or quantity of light falling on the light-sensitive parts 12 (photodiodes 13 ) are accumulated therein, regardless of the wavelength (color) of the striking light. Accordingly, if the signal charges accumulated in the light-sensitive parts 12 are used as a luminance signal, a resolution similar to that of a conventional monochromatic imaging solid-state component without a color filter is achieved.

The light is caused to also hit the vertical transfer parts 14 via the color filters 18 R , 18 G and 18 B , so that the electrical charges corresponding to the amounts of these color components are accumulated in the vertical transfer parts 14 . The signal loads, which are signals corresponding to the color components transmitted through the respective color filters, are used as a color signal.

The amount of information that is called the color signal of three Primary colors obtained is one third of the Information of the luminance signal. However, since the human eyesight is more sensitive to luminance than to Color, the amount of color information can be sufficient to be viewed as.

Thus, according to the present invention, an idea  les color signal and an ideal luminance signal correspond according to the characteristics of human eyesight through a single imaging solid-state component can be obtained at high density.

In order to further increase the resolution of the luminance signal, it is necessary to lower the resolution of the color signal within a permissible limit in order to obtain the luminance signal from the vertical transfer parts 14 . The color filters are namely thinned on the vertical transfer parts 14 or less are provided so that the color signal is obtained by the vertical transfer parts 14 on which the color filters are provided, and the luminance signal is obtained by the light-sensitive parts 12 and the vertical transfer parts 14 that have no color filter.

In the case of a monochromatic image, no color filter is necessary and, accordingly, the luminance signal can be obtained from all light-sensitive parts 12 and vertical transfer parts 14 .

Fig. 3 shows a block diagram of a control system of an electronic still camera in which an imaging solid state device in accordance with the present invention is NiO.

The light transmitted through a photographic lens 21 falls on the imaging solid-state component 10 via an aperture 22 and a mechanical shutter 23 .

The aperture 22 and the mechanical shutter 23 are controlled by a driver circuit 28 , which in turn is controlled by an MPU 25 . The MPU 25 is a microcomputer that performs overall control or general control of the electronic still camera.

The imaging solid-state component 10 is controlled by a CCD driver clock generator 26 , which is controlled by the MPU 25 and a V driver 27 , the transfer pulses or transfer pulses Φ V 1 ∼ Φ V 4 to the transparent electrodes Φ V 1 ∼ Φ V 4 outputs in accordance with the driver or drive pulses V 1 ∼ V 4 , which are output from the clock generator 26 . The transfer pulses Φ V 1 ∼ Φ V 4 are trivalent signals with three levels "L", "M" and "H".

When the transfer pulses Φ V 1 and Φ V 2 and the transfer pulses Φ V 3 and Φ V 4 are changed or changed periodically to "M" and "L" at a predetermined phase, the color signal charges or accumulated in the vertical transfer parts 14 the luminance signal charges transferred from the photosensitive parts 12 are successively transferred to the horizontal transfer part 16 . The transfer pulses Φ V 1 ∼ Φ V 4 of the levels "M" and "L", which are changed periodically, are reading pulses.

When all the transfer pulses Φ V 1 ∼ Φ V 4 become "H", the luminance signal charges accumulated in the photosensitive parts 12 are transferred to the vertical transfer parts 14 at once. The transfer pulses Φ V 1 ∼ Φ V 4 with the level "H" are accumulation control pulses (vertical transfer pulses) TG .

If the transfer pulses Φ V 1 and Φ V 2 are maintained at the "M" level, and the transfer pulses Φ V 3 and Φ V 4 are maintained at the "L" level, the color signal charges among the transparent electrodes become the Φ V 1 ∼ Φ V 4 of the vertical transfer parts 14 accumulated by the striking object light, which is transmitted through the color filter 18 . The luminance signal charges are accumulated in the light-sensitive parts 12 (photodiodes 13 ). The transfer pulses Φ V 1 ∼ Φ V 4 with the level "M" and "L" are accumulation pulses.

The accumulation pulses, the accumulation control pulses TG and the read pulses are normally output periodically by the clock generator 26 (with a cycle of approximately 1/60 sec.), So that the color signal charges accumulated periodically in the vertical transfer parts 14 are read out and those in the light-sensitive parts 12 accumulated luminance signal charges are transferred to the vertical transfer parts 14 to be read out. When the trigger is actuated, the accumulation pulses, the accumulation control pulses TG and the read pulses are output from the clock generator 26 at a predetermined timing under the control of the MPU 25 .

The signal charges transferred from the vertical transfer parts 14 to the reading part 16 are successively read from the terminal of the reading part 16 in units from a horizontal line in accordance with the read pulses output from the clock generator 26 .

The color signal, which is read from the solid-state imaging device 10 in accordance with the pulses output from the clock generator 26 and the V driver 27 , is temporarily stored in a sample-and-hold circuit (S / H) 29 , so that the stored signal is output to the sample-and-hold circuits (S / H) 30, 31 and 32 which are independently seen for the three colors R , G and B via an electronic selection switch 24 to be stored separately. The switching operation of the electronic selection switch 24 is controlled by the MPU 25 .

The color signals (analog signals), which are separately stored in the sample-and-hold circuits 30 , 31 and 32 , are sequentially converted into digital signals by a matrix circuit 36 and an A / D converter circuit 37 , so that the digital signals are sequentially in a memory (RAM) 38 can be stored.

On the other hand, the luminance signal charges that are read by the imaging solid-state component 10 are output from the electronic selection switch 24 to a signal processing circuit 33 .

Only the luminance signal is output to a recording and reproducing circuit 35 as an image data generating device via the signal processing circuit 33 controlled by the MPU 25 and a low pass filter (LPF1) 34 . The low-pass filter (LPF1) 34 is a type of band filter which only passes the luminance signal from the signals output from the signal processing circuit 33 .

The color signal stored in the memory 38 is read in synchronism with the output of the aforementioned luminance signal to be stored as a color difference signal in the recording and reproducing circuit 35 through an A / D converter circuit 39 and a low pass filter (LPF2) 40 .

The luminance signal and the color difference signal output from the low-pass filters 34 and 40 are FM-modulated in the recording and reproducing circuit 35 with predetermined carrier waves so as to be recorded on a floppy disk (recording medium) 43 as multi-modulated signals . It should be noted that the rotation of the floppy disk 43 is controlled by a motor 42 , which in turn is controlled by a drive circuit 41 . The MPU 25 functions as a recording device and an image data generating device.

The electronic still camera constructed or described above works to record a color image of high resolution as follows (see particularly Figs. 3, 4 and 5). FIGS. 4 and 5 show a flowchart of stems and a time chart of the operation of Steuersy shown in Fig. 3. The following operations are controlled by a control program that is stored in the memory of the MPU 25 .

When the trigger (not shown) is depressed in step S 51 , the MPU 25 detects the luminance of a subject to be set to adjust the aperture 22 in accordance with the luminance data (steps S 52 and S 53 ).

After the aperture setting is completed at step S 54 , control proceeds to step S 55 , at which it is checked whether the pulse VD periodically output from the clock generator 26 becomes "H".

When the pulse VD = "H", the accumulation pulses are supplied to the transparent electrodes Φ V 1 ∼ Φ V 4 of the imaging solid-state component 10 shown in FIG. 1 by the V driver 27 . Namely, the voltage of the level "M" and the voltage of the level "L" are supplied to the transparent electrodes Φ V 1 , Φ V 2 and the transparent electrodes Φ V 3 , Φ V 4, respectively (step S 56 ). As a result, the electric charges under the transparent electrodes Φ V 1, Φ V 2 of the vertical transfer parts 14 can be accumulated.

Hereinafter, the mechanical shutter 23 is control circuit from the on driven 28 to the shutter (or the shutter blade) for a predetermined Ver closing time TV 0 to open, which is determined in accordance with the detected luminance (steps S 57, S 58 and S 59 ). Accordingly, an image of an object is formed on the light-receiving surface of the imaging solid body member 10 so that the electric charges corresponding to the luminance and color of the object formation are accumulated in the photosensitive members 12 and the vertical transfer members 14 .

When the shutter is closed, the accumulation of the signal charges of the light-sensitive parts 12 and the vertical transfer parts 14 is completed. Here, after the read pulse is the transparent electrodes Φ V 1 ~ Φ V 4 supplied from the V driver 27, so that the charges accumulated in the vertical transfer parts 14 color signal charges successively read out to be stored cher in the SpeI 38th The storage is effected by the sample-hold circuits 28, 30, 32, the matrix circuit 36 and the A / D converter circuit 37 (step S 60 ).

After the writing or storage of the memory 38 is completed, the accumulation control pulses TG are output by the clock generator 26 to the transparent electrodes Φ V 1 ∼ Φ V 4 in order to transmit the luminance signal charges to the vertical transfer parts 14 . As a result, the luminance signal charges accumulated in the light sensitive parts 12 of the imaging solid state member 10 are transferred to the vertical transfer parts 14 at once.

Thereafter, the read pulses are output from the clock generator 26 to the vertical transfer parts 14 so that the luminance signal charges to the signal processing circuit 33 are output. The high frequency noise of the luminance signal processed by the signal processing circuit 33 is eliminated in the low pass filter 34 to output the luminance signal to the recording and reproducing circuit 35 (step S 62 ).

In synchronism with the output of the image luminance signal, the color signal written in the memory 38 is read out and converted by the D / A converter circuit 39 into the analog signal, so that the high-frequency noise is eliminated by the low-pass filter 40 in order to transmit the color signal to the recording and reproducing circuit 35 issue. In the recording and reproducing circuit 35 , the luminance signal and the color signal are FH-modulated and multiplied in a synchronous manner on predetermined carrier waves to be recorded as multi-modulated signals on the floppy disk 43 via the magnetic head 44 (steps S 63 and S 64 ).

As mentioned above and as seen from the foregoing, the invention aimed at the photoelectric converter function and the accumulation function of electric charges of the vertical transfer parts 14 . In the illustrated embodiment, since the color signal and the luminance signal are obtained from the vertical transfer parts 14 and the light-sensitive parts 12 , respectively, it is possible to realize a higher horizontal resolution by means of the imaging CCD component, which has the same number of picture elements as in the state of the technique.

Although the foregoing description is directed to an electronic still camera having a solid-state imaging device in which the color signal and the luminance signal are output from the vertical transfer parts 14 and the photosensitive parts 12 , respectively, the present invention is not limited to this. For example, it is possible to obtain the luminance signals and the color signals from the vertical transfer parts 14 on which no color filters are provided, and from the photosensitive parts 12 on which the color filters are provided (see FIG. 1B). In this alternative, the luminance signals read by the vertical transfer parts are first successively stored in the memory 33, and then the stored luminance signals are synchronously superimposed on the color signals of the photosensitive parts 12 .

As can be seen from the foregoing, according to the present invention both the color signals also the high density luminance signals of one receive individual imaging solid-state device.

Since there is still no possibility according to the invention, the amount of light striking the light received the surfaces of the photosensitive parts Have color filters, or on the vertical transfer parts, that have no color filters highly sensitive luminance signals can be obtained.

Since in addition the color signals and the luminance signals according to the invention are obtained independently of one another, can the color signals with a high color rendering ability and a high S / N ratio and the luminance high resolution signals can be obtained.

With an electronic still camera, which he imaging solid-state component according to the invention an image of high resolution can be formed.  

Only one imaging solid-state component is in one electronic single image camera according to the invention turned on builds, resulting in an inexpensive electronic Still camera leads.

Claims (13)

1. imaging solid-state component, comprising:

• - Photosensitive parts which accumulate electric charges in accordance with the amount of light received by them, and vertical transfer parts which accumulate electric charges in accordance with the amount of light received by them and which transmit the electric charges accumulated by the photosensitive parts;
• - The light-sensitive parts and the vertical transfer parts are placed alternately in the horizontal direction;

characterized,

• - That transparent electrodes on each of the light receiving surfaces of the vertical transfer parts are provided; and
• - that color filters with three colors are provided, the color filter alternately in a vorbe agreed order on the photosensitive Parts or the vertical transfer parts arranged are assigned to the three colors by this let through.

2. Imaging solid-state component, comprising:

• - A single integrated circuit on which vertically extending photosensitive members having a large number of picture elements to accumulate electric charges according to the amount of light they receive, and vertically extending vertical transfer members that receive electric charges according to the ones they receive Accumulate the amount of light alternately arranged in the vertical direction and close to each other so that the light-sensitive parts and the vertical transfer parts accumulate the electric charges and read the electric charges in accordance with pulses applied to electrodes that are on the light-receiving surfaces of the photosensitive parts and the vertical transfer parts are provided;
• - The electrodes on the picture elements of the light-sensitive parts and the vertical transfer parts are transparent electrodes through which visible light can be transmitted; and
• - Color filters with three colors are arranged alternately in a predetermined sequence on the light-receiving surfaces of the vertical transfer parts in order to let the assigned three colors pass through them.

3. Imaging solid-state component according to An saying 1 or 2, characterized in that the three Colors are the primary colors red, green and blue. 4. Imaging solid-state component according to An say 1 or 2, the three colors yellow, cyan and Are magenta. 5. Imaging solid-state component according to An say 1 or 2, the three color filters alternating in a strip arrangement for each vertical transfer are partially arranged. 6. Imaging solid-state component according to An saying 1 or 2, characterized in that the three Color filters alternately in a strip arrangement for  each photosensitive part are arranged. 7. Electronic still camera, comprising:

• a photographic lens and a solid-state imaging device according to claim 1 or 2, on which an object image is formed on the light-receiving surfaces thereof by the photographic lens,
• - A color signal storage device for storing color signal data, which are generated by the vertical transfer parts of the imaging solid-state component; and
• - An image signal generating device for synchronizing the luminance signals that are generated by the light sensitive parts of the imaging solid state element and the corresponding color signal data stored in the color signal storage device to generate or form object image signals.

8. Electronic still camera according to claim 7, characterized in that a pulse generation device is provided for dispensing accumulator ion pulses for accumulating the luminance signal charges in the photosensitive parts of the imaging feast body component and for accumulating the color signal charges in the vertical transfer parts, from reading pulses for reading the accumulated in the vertical transfer parts th signal charges and accumulation control pulses to transfer the in the photosensitive parts accumulated signal charges to the vertical transfer parts. 9. An electronic single-image camera comprising a photographic lens and an imaging solid component according to claim 1 or 2, on which an object image is formed on the light-receiving surfaces thereof by the photographic lens,

• - A luminance signal storage device for storing luminance signals generated by the vertical transfer parts of the imaging solid-state component; and
• - An image signal generating device for synchronizing the color signals generated by the light-sensitive parts of the imaging solid-state component and the corresponding luminance signals, which are stored in the luminance signal storage device to form object image signals.

10. Electronic still camera according to claim 9, characterized in that it further comprises a pulse generator for outputting battery simulation pulses for accumulating the color signal charge gene in the light-sensitive parts of the imaging Solid state component and for accumulating the Lumi charges in the light sensitive parts of the imaging solid-state component, of reading pulses for reading the accumulated in the vertical transfer parts th signal charges and accumulation control pulses for transferring the color signal charges that are in the light sensitive parts are accumulated on the vertical transfer parts. 11. Electronic still camera according to claim 7 or 9, characterized by a modulation direction for modulating the image signal generation supply device generated image signals to multiply generate modulated or multi-modulated signals. 12. Electronic still camera according to claim 7 or 9, characterized by a magnetic plate which the multi-modulated signals are to be recorded,  and by a recording device for recording of the multi-modulated signals on the magnetic disk.