JPH04252657A - Color image input device - Google Patents

Abstract

PURPOSE:To read a color image at a high speed and to resolve the complicated control required for color separation by simultaneously forming images, which are subjected to color separation, on photoelectric transducers in parallel by plural image forming systems. CONSTITUTION:The surface of a document 3 placed on a platen 2 is illuminated with a white light illuminating device la, and generated reflected light 7 from the document surface is led to image forming systems 5a to 5c, which are so coated that only light having a specific wavelength is allowed to pass through, by a mirror 4. Document images subjected to color separation are simultaneously formed on photoelectric transducers 6a to 6c. By this constitution, the complicated control required for color separation in a conventional device is resolved, and a memory for color correction processing is omitted.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a color separation method for a color image input device using a line sensor or the like.

0002

2. Description of the Related Art Conventionally, several methods have been studied as means for inputting color images in image input devices using line sensors such as CCDs.

For example, as shown in FIG. 5, three lighting devices 1b, 1c, and 1d that emit specific wavelengths of RGB are sequentially turned on,
The document surface 3 placed on the document platen glass 2 is illuminated to obtain color-separated document surface reflected light 7. The document surface reflected light is guided by the mirror 4 to the imaging system 5d, and is then reflected onto the photoelectric conversion element 6e. To,
Color-separated RGB images were sequentially formed.

In another example, as shown in FIG. 6, an illumination device 1a using a white light source illuminates a document surface 3 placed on a document table glass 2, and the reflected light 7 is sent to an imaging system 5 by a mirror 4.
d to form an image on the photoelectric conversion element 6e. Color separation is then performed by sequentially inserting RGB filters 8 between the document surface and the imaging system of the above-mentioned apparatus.

[0005]

[Problem to be Solved by the Invention] In the above-mentioned image input device, when trying to obtain full color for each line, R
In the method using three GB lighting devices, the three lighting devices are blinked for each line, but it is necessary to synchronize the blinking. In addition to the actual lighting time, the time required for the light intensity to stabilize after the lighting device is turned on, and the time for the afterglow to disappear after the lighting device is turned off, are required, and there is a limit to the reading speed.

[0006] Furthermore, when using RGB three-color filters, a mechanism is required to operate the filters, and as mentioned above, a mechanism is required.
It is necessary to synchronize filter insertion for each line.

[0007] In addition to the method of obtaining full color for each line, there is a method of reading the required range of the original for each color and then combining original images of each color to obtain full color.
In both cases where a three-GB illumination device is used and when a three-color RGB color filter is used, one round trip is required to read each color of RGB, and a total of three round trips are required, so there is a limit to the reading speed.

Furthermore, in the conventional color separation method, information for each color is provided in chronological order, so in order to perform color correction processing that requires full color information, for example, the data for each color must be temporarily stored. Memory was required to hold it.

[0009] The prior art had the above-mentioned problems. The present invention is intended to solve these problems, and its purpose is to enable high-speed reading, eliminate the complicated control required for color separation, and retain data for each color. This eliminates the need for memory for

0010

[Means for Solving the Problems] A color image input device of the present invention includes a document table glass, an illumination device using a white light source, a photoelectric conversion element, and an imaging system, and illuminates the document surface by illuminating it. In an image input device, a plurality of imaging systems are arranged in parallel, and the same image is formed in parallel on one or more photoelectric conversion elements. form an image. Color separation is performed by disposing in each of the plurality of imaging systems a filter that transmits or reflects only a specific wavelength in the optical path of each of the plurality of imaging systems.

[0011]

[Operation] According to the above-mentioned structure of the present invention, a plurality of imaging systems having color separation ability and one or more photoelectric conversion elements can simultaneously output color-separated images to the photoelectric conversion elements. Since the images are formed in parallel, high-speed reading is possible, and there is no synchronization required with conventional methods of inserting filters and blinking illumination devices.

0012

Embodiments will be explained below based on the drawings.

FIG. 1 is a cross-sectional view (a) in the sub-scanning direction and a cross-sectional view (b) in the horizontal direction of a color image input device according to the present invention. The white light illumination device 1a illuminates the document surface 3 placed on the document table 2, and the generated document surface reflected light 7 is reflected onto the mirror 4.
leads to imaging systems 5a, 5b, and 5c. The imaging systems are each coated with a coating to transmit only specific wavelengths, so that color-separated original images can be simultaneously formed on the photoelectric conversion elements 6a, 6b, and 6c.

[0014] As another example, FIGS. 2(a) and 2(b) show
A cross-sectional view in the sub-scanning direction and a cross-sectional view in the horizontal direction will be shown and explained.

The white illumination device 1a illuminates the document surface 3 placed on the document table 2, and the generated document surface reflected light 7 is guided to the imaging systems 5a, 5b, and 5c by the mirror 4, but the device RGB on the front of the imaging system instead of coating the imaging system
A color separation filter 14 is installed, and color-separated images can be formed in parallel on the photoelectric conversion element 6d.

The same three parallel images formed on the photoelectric conversion elements 6a, 6b, 6c or 6d can be obtained.

The contents will be explained below with reference to FIG. Figure 3
In (a), a building 11a is photographed with a camera 9a. 11b represents a plan view of the building, 11c represents a front view of the building, and the lens focus is set to 10. The image obtained in this case is 12a in FIG. 3(b), but a perspective view image with different magnifications for the top and bottom of the building is obtained, and the focused position is within the center 13 of the building.

In FIG. 4(a), the building 11a is still photographed, but the film, which is the imaging plane, is set parallel to the building, and the lens is moved parallel to the film, like the camera 9b. Yes, this is a method of taking photos called ``tilt''. In that case, the image obtained is Fig. 4(b) Photo 12b
As shown in the figure, a regular projection image with the same magnification for both the top and bottom is obtained, and the entire building is in focus.

By using this "tilt", the image input device can obtain a plurality of identical images.

[0020]

Effects of the Invention As described above, the color image input device according to the present invention can simultaneously produce color-separated images using a plurality of imaging systems having color separation capabilities and one or more photoelectric conversion elements. Since the image is formed on a photoelectric conversion element, high-speed color image reading is possible, and it is also necessary for the method of sequentially blinking the lighting device and the method of sequentially inserting filters.
There is no need to synchronize, making control easier.

Furthermore, it is possible to obtain full color information at the same time, which has the effect of saving memory for performing color correction processing.

[0022] In addition, individual lenses can be manufactured exclusively for light with wavelengths within a narrow range, and the problem of chromatic aberration, which degrades lens resolution and makes lens design difficult, can be easily solved. Can be cleared.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a color image input device according to the present invention.

FIG. 2 is a sectional view of another embodiment of the color image input device according to the present invention.

FIG. 3 is an explanatory diagram showing the characteristics of image formation.

FIG. 4 is an explanatory diagram showing the characteristics of image formation.

FIG. 5 is a sectional view of a conventional color image input device.

FIG. 6 is a sectional view of a conventional color image input device.

[Explanation of symbols]

1a White light source lighting device 1b R color lighting device 1c G color lighting device 1d B color lighting device 2. Manuscript table glass 3　　　　　　　　Manuscript surface 4 Mirror 5a First imaging system 5b Second imaging system 5c Third imaging system 6a First photoelectric conversion element 6b Second photoelectric conversion element 6c Third photoelectric conversion element 6e Photoelectric conversion element 6d Photoelectric conversion element 7. Light reflected from the original surface 8 RGB filter 9a　　　　Photograph machine 9b Tilt camera 10 Focus position 11a Building 11b Building floor plan 11c Building front view 12a Photo of perspective drawing law form 12b Photo of regular diagram 13 Focus range 14 RGB filter

Claims (1)

[Claims] 1. A document platen glass, an illumination device using a white light source, a photoelectric conversion element, and an imaging system. A color image input device that forms an image on a conversion element includes a plurality of lined-up imaging systems, a reflective or transmissive color separation filter placed in the optical path of each of the imaging systems, and a color separation filter corresponding to the imaging system. A color image input device characterized by being equipped with a photoelectric conversion element.