JPH08130748A - Color still picture photographing device - Google Patents

Abstract

PURPOSE: To irradiate an object with the light of the color with sufficient light quantity at the time of picking up the images of the pictures of the respective colors by letting a second strobe emit the light in the same color as the light emission color of a first strobe when the first strobe emits the light. CONSTITUTION: The first strobe 10 which is a master light source successively emits the light of red(R), blue(B) and green(G) whose luminance is approximately equal by a first strobe control circuit 12. When the strobe 10 emits the light, second and third strobe control circuits 24 and 26 detect the change of the light quantity and the light emission color, respectively control second and third strobes 28 and 30 which are respectively strobe light sources and let them emit the light in the same light emission color as the strobe 10. The light from the strobes 10, 28 and 30 illuminates a photographing object 22 and a monochrome video camera 14 photographs the object 22 through a lens. Thus, without providing a filter in front of the camera 14, by using a single camera 14 along with the plural strobes for obtaining sufficient irradiation light, the color video signals of a still object are generated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color still image capturing apparatus for generating a still image color video signal using a single monochrome video camera.

[0002]

2. Description of the Related Art Generally, a color image
A video camera is used. A color video camera has one image sensor (for example, CCD) in red,
There are a single plate type commonly used for blue and green three primary color lights, and a three plate type using dedicated image pickup devices for each of the three primary color lights.
The single plate type has an advantage that the configuration is simple and inexpensive, but has a drawback that it is difficult to increase the resolution for a color image. On the other hand, the three-plate type has a high resolution, but has a drawback that it is expensive because the mounting accuracy is high and the structure is complicated, and the adjustment for matching the characteristics of the three image pickup devices is troublesome.

Images input by a video camera for printing or the like are still images, but high resolution is required. Therefore, it has been conventionally practiced to take a color still image using a monochrome video camera. In this case, the color filters of the three primary colors of red, blue and green are sequentially arranged in front of the lens of the monochrome video camera, and in order to obtain a clear image, normally multiple white light strobes are emitted at the same time. , The red component, the blue component, and the green component of the color image are sequentially captured, and the three captured monochrome video signals are combined to form a color video signal. Although the red component, the blue component, and the green component of the color image are deviated at the time of photographing, since the object to be photographed is a still image, there is no change in the image over time, so there is no problem at the time of photographing. On the other hand, since a single monochrome video camera is enough, the configuration is simple and inexpensive, and
The resolution is high as in the 3-plate type.

[0004]

In a conventional color still image capturing apparatus using a monochrome video camera, three types of color filters of red, blue and green are attached to a disc, and the disc is stepped.・ The color filter was switched by rotating the motor. That is, since the filter is mechanically switched in front of the monochrome video camera, vibration may occur during the switching, which may affect the placement of the video camera. Therefore, the relative position between the object to be photographed and the video camera may change with the passage of time. In this case, even for a still image, a color shift occurs due to a change in the relative position between the video camera and the object to be photographed. This is because the higher the resolution,
A large impact.

In front of the monochrome video camera,
The applicant of the present application is also studying a method of removing an influence of vibration by providing an electronic filter and electrically changing the characteristics of the electronic filter. However, in this method, the electronic filters have unequal transmissivities when passing red, blue, and green light, and the output video signal of the video camera depends on the optical transmissivity of each light component of the electronic filter. Had to be corrected.

Therefore, an object of the present invention is to
Color that can generate a color video signal of a stationary object using a single monochrome video camera with multiple strobes firing simultaneously for sufficient illumination without a filter in front of the video camera To provide a still image capturing device.

[0007]

A color still image pickup device of the present invention comprises a monochrome video camera,
First and second strobes which emit red, blue and green light;
A first control circuit that controls the first strobe to sequentially emit red, blue, and green light in response to the operation of the shooting switch; and, when the first strobe emits light, detects the emission color, A second control circuit for controlling the second strobe to emit light of the same color as the first strobe; and a video control when the first and second strobe emit red, blue and green light.
And a capturing / combining circuit for sequentially capturing the output video signals of the camera and synthesizing them to form a color video signal.
When the first strobe emits light, the second strobe also emits the same color as the emitted color. Therefore, when capturing an image of each color, a sufficient amount of light of that color can be applied to the object. it can.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a block diagram of the device of the present invention.
Under the control of the first strobe control circuit 12, the first strobe 10, which is a master light source, sequentially emits light of red color (R), blue color (B), and green color (G), which have almost the same brightness. It emits light. When the first strobe 10 emits light, the second and third strobe control circuits 24 and 26 detect the change in the light amount and the emission color and control the second and third strobes 28 and 30, which are slave light sources, respectively. Then, the first strobe 10 is made to emit the same emission color. The light from the strobes 10, 28 and 30 illuminates the object 22 to be photographed. Also,
The monochrome video camera 14 shoots the shooting target 22 through the lens. The image capturing / synthesizing circuit 16 causes the strobe control circuit 1 to operate each time the photographing switch 20 is turned on.
2 causes the strobe 10 to emit light, captures the video signal from the monochrome video camera 14, synthesizes the three monochrome video signals when red, blue, and green lights are emitted, and a circuit used by a printer or the like. Output to 18. It is preferable that the light sources (strobes) 10, 24, 28, the video camera 14 and the object to be photographed 22 are arranged in a closed dark room, but it may be a room where strong external light does not enter.

The operation of the apparatus of FIG. 1 will be further described. First,
When the operator turns on the switch 20, a light emission instruction signal is supplied from the image capturing / combining circuit 16 to the strobe control circuit 12, and the strobe 10 emits red light. In response to this, the strobes 28 and 30 also emit red light, and a sufficient amount of red light is emitted to the object 22 to obtain a clear image, and the red portion of the object 22 is irradiated. Only the light of this red color is reflected. Since the monochrome video camera 14 shoots the light reflected by the object 22,
A monochrome video signal corresponding to the red part of the object is generated. The image capturing / combining circuit 16 is provided at the time when the switch 20 is turned on, that is, the video camera 14
Captures the monochrome video signal of the red part of the target object and stores it in the red memory.

When the operator turns on the switch 20 again, a light emission instruction signal is supplied from the image capturing / combining circuit 16 to the strobe control circuit 12 to emit blue light.
In response to this, the strobes 28 and 30 also emit blue-colored light, and a sufficient amount of blue-colored light is applied to the target object 22, and only the blue-colored portion of the target object 22 has this blue-colored light. Reflects light. The monochrome video camera 14 generates a monochrome video signal corresponding to the blue color portion of the object 22, and the image capturing / combining circuit 16 captures the monochrome video signal of this blue color portion and outputs the blue color signal. Store in memory. Similarly, when the operator turns on the switch 20 for the third time, the strobe 10 emits green light in response to a light emission instruction signal from the image capturing / combining circuit 16 to the strobe control circuit 12. In response to this, the strobes 28 and 30 also emit green light, and a sufficient amount of green light is emitted to the object 22, and the monochrome video camera 14 detects A monochrome video signal corresponding to the green part is generated, and the image capturing / synthesizing circuit 16
Captures the monochrome video signal of the green color portion and stores it in the green color memory.

When the image capturing / combining circuit 16 captures the video signals corresponding to the three primary colors of light into the memories of red, blue and green, the video signals stored in the respective memories are read out at the same time and are composited to obtain a color signal. -Generate a video signal. Although the time points at which the image capturing / combining circuit 16 captures the video signals of the three primary colors are different from each other, this time difference is not a problem because the object 22 to be photographed is stationary. The combined color video signal is supplied to the utilization circuit 18 and processed according to the purpose of the utilization circuit. As an example, utilization circuit 18 is a color video printer and a color image printout of object 22 is obtained. It should be noted that when the switch 20 is turned on once, red, blue, and green lights may be sequentially and automatically emitted, and the image capturing / combining circuit 16 may sequentially and automatically capture the respective lights.

The strobes 10, 28 and 30 are the same, and FIG. 2 is a diagram showing specific examples thereof. In this specific example, a dichroic prism is used. The same light sources 200, 202 and 204, which are light emitting elements,
The prisms 206, 208, and 210 are arranged so as to face each other. The light sources 200, 202 and 204
Each of which is white light including red, blue and green light. The prisms 206 and 210 are triangular prisms, and the prism 208 is a quadrilateral prism, which are arranged as shown. The red reflective dichroic film 212 is provided on the contact surfaces of the prisms 208 and 210, and the blue reflective dichroic film 214 is provided on the prism 210 side of the prism 206. In addition, in order to totally reflect the light, the prism 2
A finely spaced air gap is provided between 06 and 210.

When the light source 200 emits light, the light passes through the inclined surface of the prism 206 to the right and is totally reflected on the vertical surface, and the blue color reflection dichroic film 2 on the inclined surface to the right and down.
Only the blue light is reflected at 14 and is output to the outside. When the light source 202 emits light, the light is emitted from the prism 20.
Red reflective dichroic film 212 passing through the vertical plane of 8
Then, only the red component is reflected, and the remaining blue and green components pass through the red reflective dichroic film 212. Further, the blue component is reflected by the blue reflection dichroic film 214, and only the green component is output to the outside. Further, when the light source 204 emits light, the light passes through the horizontal plane of the prism 210 and is totally reflected by the air gap, and only the red component is reflected by the red reflection dichroic film 212 and passes through the prisms 210 and 206. Output to the outside. Therefore, the light source 200 controls the generation of blue light, and the light source 2
02 controls the generation of green light, and the light source 204 controls the generation of red light.

By the way, the dichroic films 212 and 2
In the color separation by 14 only, when the color separation is incomplete, the color separation can be improved by using the trimming filter. In this case, a blue trimming filter 216 is provided between the light source 200 and the prism 206, and a green trimming filter 218 is provided between the light source 202 and the prism 20.
8 and a red trimming filter 220 is provided between the light source 204 and the prism 210. These trimming filters have the function of adjusting the spectral characteristics of each color, and the characteristics for the output light are as shown in FIG. As can be seen from the characteristic diagram of FIG. 3, the characteristics of the light of each color output by the light emission of each light source are surely separated, so that the blue (B), green (G), and red (R) color classifications are clear. Therefore, the sharpness of the color of the image can be emphasized. Therefore, the color from the image capturing / combining circuit 16
The color characteristics of the video signal are also clearly classified.

FIG. 4 shows a strobe control circuit 2 and a light source 28.
Shows the configuration of. The strobe control circuit 24 and the strobe control circuit 26 are the same, and the light sources 28 and 30 are the same as described above. The strobe control circuit 24 has three photosensors 32R, 32G and 32B. Each optical sensor 32
R, 32G, and 32B generate an output signal to the light source 28 when a light receiving element such as a photodiode that detects the amount of light incident on the light receiving portion and the amount of light detected by the light receiving element exceeds a certain level. Including a supply circuit. Strobe 28
Light source 200 for red, 202 for green and 204 for blue
Emits light when the output signals of the light sensors 32R, 32G, and 32B are supplied, respectively. Red, green and blue filters 34R, 34G and 34B are arranged in front of the light receiving elements of the optical sensors 32R, 32G and 32B, respectively. Red, green and blue filters 34R, 34G and 34B
Respectively allow only red light, green light and blue light to pass.
Therefore, when the master strobe 10 emits red light, only the optical sensor 32R detects the light passing through the red filter 34 and supplies the output signal to the red light source 200,
Slave strobes 28 and 30 emit red light. Similarly, when the master strobe 10 emits green or blue light, the slave strobes 28 and 30 are
It emits green or blue light. Therefore, when capturing an image of each color, a sufficient amount of light of the corresponding color can be applied to the object.

Although the preferred embodiment of the present invention has been described above, various modifications and changes can be made without departing from the spirit of the present invention. For example, the image capturing / combining circuit 16 may be a Macintosh (trademark) personal computer manufactured by Apple. In this case, the captured data can be edited in various ways. The monochrome video 14 may use an image pickup tube other than the CCD as an image pickup element. Although the video camera is monochrome, a color video camera may be used in monochrome mode.

[0017]

As described above, according to the present invention, when the first strobe emits light, the second strobe also emits the same color as the emitted color, so that when capturing an image of each color, A sufficient amount of colored light can be applied to the object.

[Brief description of drawings]

FIG. 1 is a block diagram of a preferred embodiment of the present invention.

FIG. 2 is a diagram showing a strobe used in the present invention.

FIG. 3 is a diagram showing characteristics of the strobe shown in FIG.

FIG. 4 is a diagram showing a second strobe control circuit used in the present invention.

[Explanation of symbols]

 10 First Strobe 12 First Strobe Control Circuit 24, 26 Second Strobe Control Circuit 28, 30 Second Strobe

Claims (4)

[Claims] 1. A monochrome video camera, first and second strobes for emitting red, blue, and green light, and red, blue, and green lights from the first strobe in response to operation of a photographing switch. A first control circuit for controlling so that the first strobe emits light, and when the first strobe emits light, the emission color is detected so that the second strobe emits light of the same color as the first strobe. And a second control circuit for controlling the
And a color still image capturing apparatus including a capturing / combining circuit that sequentially captures the output video signals of the video camera when the second strobe emits red, blue, and green light and synthesizes them to obtain a color video signal. . 2. The strobe comprises first, second and third light emitting elements and a dichroic film that receives light from the first, second and third light emitting elements and reflects the first and second light. To extract the light of the first, second and third colors from the light from the first, second and third light emitting elements, and use the prism to extract the first and second light.
And a dichroic prism for matching the optical paths of the third light and the color still image pickup device according to claim 1. 3. The color still image pickup device according to claim 2, wherein the dichroic prism has a red trimming filter, a blue trimming filter, and a green trimming filter. 4. The second control circuit causes the first, second and light emitting elements to emit light when detecting the red, green and blue filters and the light respectively passing through the red, green and blue filters. The color still image capturing device according to claim 2, further comprising three photosensors.