JP2003018361A - Color and reader - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an inexpensive image reader that can acquire an image of high quality and well-balanced color output. SOLUTION: The color CCD reader in an image reader of a type of using a color CCD and a white light source is provided with a means that monitors the output of each color of a color CCD and changes the period of a transfer gate of each color for one raster so as to adjust the exposure time. Thus, the color CCD reader can acquire an image with high quality and well-balanced color output by means of a simple means.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color CCD (Charge C) for copying machines, facsimiles, image scanners, and the like.
The present invention relates to a color CCD reading device provided in a device for reading an image by means of an coupled device, and in particular, when using a color CCD having no shutter gate function, RGB (Re
(d, Green, Blue) The present invention relates to a color CCD reader provided with a means for controlling the amount of received light.

[0002]

2. Description of the Related Art A color CCD reading device in an image reading device of a type using a conventional color CCD and a white light source will be described with reference to FIGS.

FIG. 9 is a diagram showing a configuration example of a conventional color CCD reading device, and FIG. 10 is a timing diagram showing a conventional color CCD reading device. In the figure, 91 is a white light source for illuminating the original,
Reference numeral 92 is a transparent original to be read, 93 is a lens that converges the light that has passed through the transparent original, 94 is a CCD that receives the converged light and converts it into an electrical signal, 95 is an amplifier that amplifies the CCD output, and 96 is the CCD output. A multiplexer for switching, 97 is an AD for converting an analog signal into a digital signal
C (Analog Digital Converter), 98 is a gain control unit that controls the gain of the amplifier, 99 is a CPU that monitors the output of the CCD, and controls the amplifier via the gain control unit so that the RBG outputs are the same, Reference numeral 100 denotes a CCD driver timing generation unit that generates each signal for driving the CCD.

In this example, the cycle of the transfer gates (R, G, B) generated by the CCD driver timing generator is 1/3 of the read time of one raster as shown in FIG.
Further, the CCD outputs (R, G, B) are read by a line-sequential method (so as to sequentially shift one cycle at a time).

Further, the output of the CCD generally has a variation in the output of RGB as shown in FIG. 10B due to the spectral distribution characteristics of the white light source and the color CCD. Since the variation in the output of each color leads to the deterioration of the image quality, the variation in the output of each color is eliminated, and the amplifier is controlled so that the output of each color is almost the same as shown in FIG. It is amplified. By processing in this way, the read image quality of the image reading device is improved.

[0006]

However, the conventional color CCD reading device shown in FIG. 9 adjusts each light reception output of RGB by an amplifier, which also amplifies noise and reads a high-quality image. However, there is a problem in that it is not suitable for the image reading apparatus.

Further, there is an image reading apparatus using a color CCD provided with a sitter gate function for adjusting the exposure time of RGB (the CCD output is set to the same level by adjusting the exposure time), but it has a sitter gate function. CCD
However, there is a problem that the image reading device becomes expensive because it is very expensive.

[0008]

SUMMARY OF THE INVENTION The present invention has been made in consideration of the above problems, and is a color CCD reading device in an image reading device of a type using a color CCD and a white light source. Monitor the output of each color, and make sure that the output of each color is almost the same.
Means for adjusting the exposure time of each color of the CD, adjusting the amount of light emitted from the white light source, or adjusting the amount of light emitted from the white light source is provided. As a result, a high-quality image in which the output of each color is balanced can be obtained by an inexpensive means.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION (1) Color CCD in an image reading apparatus of a type using a color CCD and a white light source
The reading device is provided with means for monitoring the output of each color of the color CCD and adjusting the exposure time by changing the cycle of the transfer gate of each color in one raster so that the output of each color is substantially the same. As a result, a high-quality image in which the output of each color is balanced can be obtained by an inexpensive means.
Further, it is possible to provide an inexpensive image reading device capable of obtaining a high quality image.

(2) In a color CCD reading device in an image reading device of the type that uses a color CCD and a white light source, the output of each color of the color CCD is monitored and the white light source is set so that the output of each color becomes almost the same. A means for adjusting the amount of emitted light is provided. As a result, a high-quality image in which the output of each color is balanced can be obtained by an inexpensive means. Further, it is possible to provide an inexpensive image reading device capable of obtaining a high quality image.

(3) In the color CCD reader described in (2), there is provided means for adjusting the amount of light emitted by the white light source by adjusting the voltage applied to the white light source. This allows
It is possible to obtain a high-quality image in which the output of each color is balanced.

(4) In the color CCD reader described in (2), there is provided means for adjusting the amount of light emitted by the white light source by adjusting the on / off duty of the voltage applied to the white light source. This makes it possible to obtain a high-quality image in which the output of each color is balanced.

(5) In a color CCD reading device in an image reading device of a type that uses a color CCD and a white light source, the output of each color of the color CCD is monitored and the white light source is set so that the output of each color becomes almost the same. A means for adjusting the amount of light emitted from the white light source is provided by blocking the light with a liquid crystal shutter. As a result, a high-quality image in which the output of each color is balanced can be obtained by an inexpensive means. Also,
It is possible to provide an inexpensive image reading device that can obtain a high-quality image.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIGS. 1 and 2, the color CC of the present invention.
A first embodiment of the D reading device will be described.

FIG. 1 is a block diagram (1) of an embodiment of a color CCD reader of the present invention, and FIG. 2 is a timing diagram (1) of the color CCD reader. In FIG. 1, 1 is a white light source for illuminating an original, 2 is a transparent original to be read, 3 is a lens for converging the light passing through the transparent original, 4 is a CCD for receiving the converged light and converting it into an electric signal, 5 Is a buffer amplifier for CCD output, 6 is a multiplexer for switching CCD output, and 7 is AD for converting an analog signal into a digital signal
C and 9 monitor the output of the CCD and adjust the cycle of the transfer gate so that the output of each color of the CCD is almost the same.
A CPU that controls the amount of light received by D, 10 is a CCD driver timing generation unit that generates each signal for driving the CCD, and 8A and 8B count the pulses of the transfer clock, and the count value is set by the CPU. It is a counter that sometimes generates pulses for the transfer gates R and G.

In this example, the transfer gate signal generated by the CCD driver timing generator is input as the transfer gate B signal of the CCD 4 and also as the clear signal of the counters 8A and 8B. Also,
The output of the counter 8A is input as the transfer gate R signal of the CCD 4, and the output of the counter 8B is input as the transfer gate G signal of the CCD 4.

FIG. 2 shows control of the transfer gate cycle when the CCD output is R>G> B. In this example, the counter 8A sets a count value so that the counter 8A generates a pulse at the timing of arrow A, and the counter 8B sets a count value so that the counter 8B generates a pulse at the timing of arrow B. . By controlling in this way, each cycle of the transfer gates R, G, B is adjusted, that is, the exposure time of each color of the CCD is adjusted to C.
The amount of light received by the CD is adjusted so that the output of each color of the CCD is substantially the same.

Thus, for example, when reading the white reference,
Means is provided for monitoring the output of each color of the color CCD and adjusting the exposure time by changing the cycle of the transfer gate of each color in one raster so that the output of each color is substantially the same. As a result, a high-quality image in which the output of each color is balanced can be obtained by an inexpensive means.

Next, a second embodiment of the color CCD reading device of the present invention will be described with reference to FIGS.

FIG. 3 is a block diagram (2) of an embodiment of the color CCD reader of the present invention, and FIG. 4 is a timing diagram (2) of the color CCD reader. In addition, 1 to 7 and 1 in FIG.
0 is the same as 1 to 7 and 10 in FIG.

Further, 11 in FIG. 3 is a light source applied voltage control unit for controlling the applied voltage of the white light source, and 12 is a CC at the time of factory shipment.
An applied voltage storage unit that stores the applied voltage of the white light source adjusted so that the output of each color of D is almost the same, and 9 is a CCD
Is a CPU that controls the amount of light emitted from the white light source by adjusting the voltage applied to the white light source through the light source application voltage control unit so that the output of each color of the CCD becomes substantially the same. The CPU 9 controls the applied voltage of the white light source based on the applied voltage stored in the applied voltage storage unit.

FIG. 4 shows the control of the voltage applied to the light source when the CCD output is R>G> B. In this example, the applied voltage of the white light source is set to 12 V according to the exposure time of arrow A.
Then, the applied voltage of the white light source is controlled to 13.5V according to the exposure time of arrow B, and the applied voltage of the white light source is controlled to 15V according to the exposure time of arrow C to adjust the amount of light emitted by the white light source. By adjusting the amount of light received by the CCD,
The output of each color of D is made substantially the same.

Thus, for example, when reading the white reference,
Means is provided for monitoring the output of each color of the color CCD and adjusting the amount of light emitted by the white light source so that the output of each color is substantially the same. As a result, a high-quality image in which the output of each color is balanced can be obtained by an inexpensive means.

Next, a third embodiment of the color CCD reading apparatus of the present invention will be described with reference to FIGS.

FIG. 5 is a block diagram (3) of an embodiment of the color CCD reader of the present invention, and FIG. 6 is a timing chart (3) of the color CCD reader. In addition, 1 to 7 and 1 in FIG.
0 is the same as 1 to 7 and 10 in FIG.

Reference numeral 13 in FIG. 5 is a light source applied voltage duty control section for controlling the duty of the applied voltage of the white light source,
14 is a duty storage unit that stores the duty of the applied voltage of the white light source adjusted so that the output of each color of the CCD is almost the same at the time of factory shipment. 9 monitors the output of the CCD, and the output of each color of the CCD is almost the same. The duty of the applied voltage of the white light source is adjusted through the light source applied voltage duty control unit so as to be the same, and the light amount emitted from the white light source is controlled C
It is PU. The CPU 9 controls the duty of the applied voltage of the white light source on the basis of the duty of the applied voltage stored in the duty storage unit.

FIG. 6 shows the control of the duty of the light source applied voltage when the CCD output is R>G> B. In this example, the duty of the applied voltage of the white light source is set to 50% in accordance with the exposure time of arrow A, the duty of the applied voltage of the white light source is set to 70% in accordance with the exposure time of arrow B, and the exposure time of arrow C is set. In addition, the duty of the applied voltage of the white light source is controlled to be 90%, and the light receiving amount of the CCD is adjusted by adjusting the light amount emitted by the white light source so that the output of each color of the CCD becomes substantially the same. There is.

Thus, for example, when reading the white reference,
Means is provided for monitoring the output of each color of the color CCD and adjusting the amount of light emitted by the white light source so that the output of each color is substantially the same. As a result, a high-quality image in which the output of each color is balanced can be obtained by an inexpensive means.

Next, a fourth embodiment of the color CCD reading apparatus of the present invention will be described with reference to FIGS.

FIG. 7 is a block diagram (4) of an embodiment of the color CCD reading device of the present invention, and FIG. 8 is a timing diagram (4) of the color CCD reading device. In addition, 1 to 7 and 1 in FIG.
0 is the same as 1 to 7 and 10 in FIG.

Reference numeral 16 in FIG. 7 is provided between the white light source 1 and the transparent original 2, and the light emitted from the white light source 1 is transmitted through the transparent original 2.
The liquid crystal shutter that allows the liquid crystal shutter to pass through and shut off, the liquid crystal shutter control unit 15 that controls the opening and closing of the liquid crystal shutter 16, and the light shielding 17 of the liquid crystal shutter that is adjusted so that the output of each color of the CCD is almost the same at the time of factory shipment. A light-shielding time storage unit for storing time, 9 monitors the output of CCD,
This is a CPU that controls the amount of light emitted from the white light source by adjusting the light blocking time of the liquid crystal shutter via the liquid crystal shutter control unit so that the outputs of the respective colors D are substantially the same. Note that C
The PU 9 controls the light blocking of the white light source based on the light blocking time stored in the light blocking time storage unit.

FIG. 8 shows the control of the liquid crystal shutter when the CCD output is R>G> B. In this example, the light blocking time of the liquid crystal shutter is set to T in accordance with the exposure time of the arrow A.
1, the light blocking time of the liquid crystal shutter is set to T2 according to the exposure time of the arrow B, and the light blocking time of the liquid crystal shutter is set to T3 according to the exposure time of the arrow C, and the amount of light emitted from the white light source is adjusted. By doing so, the amount of light received by the CCD is adjusted so that the output of each color of the CCD becomes substantially the same.

Thus, for example, when reading the white reference,
Means is provided for monitoring the output of each color of the color CCD, shielding the white light source with a liquid crystal shutter so that the output of each color is substantially the same, and adjusting the light amount emitted from the white light source. As a result, a high-quality image in which the output of each color is balanced can be obtained by an inexpensive means.

[0034]

The present invention is carried out in the form as described above and has the following effects.

In an apparatus for reading an image using a color CCD having no shutter gate function, the output of each color of the color CCD is monitored, and the exposure time of each color of the color CCD is adjusted so that the output of each color is almost the same. By adjusting the amount of light emitted from the white light source, or by adjusting the amount of light emitted from the white light source, it is possible to obtain a high-quality image in which the output balance of each color is balanced by an inexpensive means.

Further, it becomes possible to provide an inexpensive image reading apparatus capable of obtaining a high quality image.

[Brief description of drawings]

FIG. 1 is a configuration diagram (1) of an embodiment of a color CCD reading device of the present invention.

FIG. 2 is a timing chart (1) of the color CCD reading device.

FIG. 3 is a configuration diagram (2) of an embodiment of the color CCD reading device of the present invention.

FIG. 4 is a timing example diagram (2) of the color CCD reading device.

FIG. 5 is a configuration diagram (3) of an embodiment of the color CCD reading device of the present invention.

FIG. 6 is a timing example diagram (3) of the color CCD reading device.

FIG. 7 is a configuration diagram (4) of an embodiment of the color CCD reader of the present invention.

FIG. 8 is a timing chart (4) of the color CCD reading device.

FIG. 9 is a structural example diagram of a conventional color CCD reading device.

FIG. 10 is a timing example diagram of a conventional color CCD reading device.

[Explanation of symbols]

1 white light source 2 Transparent manuscript 3 lenses 4 CCD 5 buffer amplifier 6 multiplexer 7 ADC 8A counter 8B counter 9 CPU 10 CCD driver timing generator 11 Light source applied voltage control unit 12 Applied voltage storage 13 Light source applied voltage duty control unit 14 Duty storage section 15 LCD shutter control unit 16 LCD shutter 17 Shading time storage

Front page continuation (51) Int.Cl. ⁷ Identification code FI theme code (reference) H04N 1/48 H04N 1/46 A

Claims (5)

[Claims] 1. A color CCD reading device in an image reading device of a type using a color CCD and a white light source, wherein outputs of respective colors of the color CCD are monitored and respective colors in one raster are made to be substantially the same. And a means for adjusting the exposure time by changing the period of the transfer gate of the color CCD reading apparatus. 2. A color CCD reading device in an image reading device of a type that uses a color CCD and a white light source, monitors the output of each color of the color CCD, and emits the white light source so that the output of each color becomes substantially the same. A color CCD reader characterized in that it is provided with means for adjusting the amount of light. 3. The color CCD reading device according to claim 2, further comprising means for adjusting the amount of light emitted from the white light source by adjusting the voltage applied to the white light source.
CD reader. 4. The color CCD reading device according to claim 2, further comprising means for adjusting the amount of light emitted from the white light source by adjusting the on / off duty of the voltage applied to the white light source. Reader. 5. A color CCD reading device in an image reading device of a type using a color CCD and a white light source, wherein the output of each color of the color CCD is monitored and a white light source is used as a liquid crystal so that the output of each color becomes substantially the same. A color CCD reading device characterized in that means for adjusting the amount of light emitted from a white light source is provided by blocking light with a shutter.