JPS60236355A - Color picture scan reader - Google Patents

Abstract

PURPOSE:To simplify the control of the light beam quantity of >=2 colors by providing optical wedges into optical paths formed before the light beams of at least two colors are synthesized and having an interlocked action between those optical wedges. CONSTITUTION:An Ar<+> laser 2B and an He-Ne laser 4B pass through a pair of optical wedge members 11 set at the positions which cross the optical paths of both lasers before they are made incident on a dichroic mirror 12 to be synthesized. Therefore, the light quantity balance can be changed between both lasers 2B and 4B by controlling the members 11. Then a light beam 6B' equal to a light beam 6B obtained by synthesizing said two lasers is used for picture reading purposes. This ensures a desirable read scan and therefore the desirable memory reproduction.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention relates to a color image reading device that reads color images by scanning a light beam, and in particular to a color image reading device that reads color images by scanning a light beam. The present invention relates to adjusting the amount of the light beam of a color image reading device using a beam.

(Prior art) In recent years, color images have been read using light beams to obtain image signals, and after performing image corrections such as gradation conversion and sharpness enhancement, they are output to a CRT or printed on recording paper or film. Various recording systems have been developed. In such systems, color images cannot be read if only one color light beam is used for reading.
A combination of light beams of two or more colors is used as a reading light beam.

However, in conventional devices, the light intensity of the light beams emitted from the two light sources is adjusted independently, so the total light intensity of the two color light beams emitted from each light source is always kept constant. It is difficult to adjust the balance of each color while maintaining the same balance, and as the light intensity of the light beam changes due to wear and tear of the laser light source, color originals may
There has been a problem in that it is difficult to always faithfully reproduce the color tone of the original. In addition, if the color tone of the color document itself is unfavorable and you want to obtain an image with corrections to the color tone of the color document being read as a reproduced image, the light intensity (balance) of each light beam for reading may be changed. cannot be arbitrarily changed, making it difficult to obtain a desired reproduced image. Furthermore, even in a device in which an optical filter or the like is installed on the optical path before combining each light beam, and the light intensity of each light beam is adjusted by this filter, the light intensity of each light beam can be adjusted independently. Therefore, there is a drawback that the adjustment operation for determining the desired light amount becomes complicated, especially when it is desired to perform adjustment without changing the total light amount of the reading light beam.

(Object of the Invention) The present invention has been made in view of the above-mentioned problems, and it is possible to adjust the total amount of light of at least two different color light beams for reading a color document, depending on the color document to be read. It is an object of the present invention to provide a color image scanning/reading device equipped with a mechanism that allows adjustment of the light amount with a simple operation without changing the amount of light.

(Structure of the Invention) The color image scanning/reading device according to the present invention includes a light beam of at least two colors for reading a color original in an optical path before being combined.
The optical wedges are each provided with an optical wedge, and the optical wedges are interlocked by an interlocking mechanism to adjust the light amount of each beam without substantially changing the total light aperture of the two color light beams.

The color image scanning/reading device system of the present invention obtains an image signal by scanning a color original carrying a color image with a reading beam formed by combining light beams of at least two different colors. , the optical wedge is provided on an optical path before combining at least two color light beams among different light beams for image reading, and has a characteristic of not exhibiting spectral selective absorption unlike an ND filter. . In addition, the interlocking mechanism for interlocking the pair of optical wedges changes the concentration of the optical wedge with respect to the light beam in opposite directions to each other, so that the total optical aperture of the reading light beam is hardly changed. It has a structure that adjusts the relative balance of light beams over colors.

(Effects of the Invention) According to the color image scanning reading device as described above, the light intensity of the light beam of two or more colors for reading can be adjusted according to the color original to be read, so that reproduction faithful to the original can be achieved. In addition, it is also possible to correct the color tone of the document to a preferable one and then record and reproduce it. In addition, to adjust the light intensity, a pair of optical wedges are linked in advance by an interlocking mechanism so that the optical densities of each optical wedge are in opposite directions, so all you have to do is operate this interlocking mechanism. The light intensities of at least two different color light beams can be adjusted simultaneously and with almost no change in the total light intensity.

(Example) Hereinafter, the color image scanning and reading apparatus of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a principle diagram showing an example of an optical system in the apparatus of the present invention.

Ar + laser 2 (λ=514.5
nm or 488.0 nm) is randomly polarized,
an Ar+ laser 2A having a polarization direction horizontal to the optical path by a beam splitter 10 provided on the optical path;
The laser beam is divided into Ar+laser 2B having a polarization direction perpendicular to the optical path (the direction indicated by the arrow in the figure). (Here, the polarization direction horizontal and perpendicular to the optical path means the polarization direction horizontal and perpendicular to the plane including the laser 2 and the laser 4B described below.) A transparent body placed at the corner of the Eustar or one provided with an interference film can be used. On the other hand, HefQe laser 4B (λ=63
2.8 nm) is linearly polarized to have a polarization direction perpendicular to the optical path, and this He-Ne laser 4B and the Ar+ laser 2B are connected to a dichroic mirror 12 installed at a position to receive both lasers. The light is incident on the same point above from two directions perpendicular to each other. This dichroic mirror 12 has a property of reflecting a light beam having the wavelength of Ar+ laser and transmitting a light beam having the wavelength of @e-Ne laser.
2 by Ar+ laser 2B and He-Ne laser 4
B are combined on the same optical path to form a light beam 6B. This light beam 6B has both the wavelengths of the Ar+ laser and the He-IJe laser, and has a polarization direction perpendicular to the optical path (in the direction indicated by the arrow in the figure). By the way, the Ar+ laser 2B and the He-NeL/- laser 4B pass through a pair of optical wedge members 11 provided at positions intersecting the optical paths of both lasers, before entering the dichroic mirror 12 and being combined. It is supposed to be done. This optical wedge member 11 has a structure as shown in FIG.
The command is made by an interlocking mechanism consisting of c. A pair of optical wedges 11 that are slidably provided in the frame 11c and have optical density changes in opposite directions.
d and lid' are engaged with a threaded portion 11b, and can be moved up and down by rotating an adjustment knob 11a provided integrally with this threaded portion 11b. That is, when the adjustment knob 11a is moved in the direction of arrow A, the optical wedges 11d and 11d' move upward (in the direction of arrow A' in the figure), and the light intensity of the light beam incident on the optical wedge 11d side is reduced; The light intensity of the light beam incident on the wedge 11d' side increases, and when the adjustment knob 11a is moved in the direction of arrow B, the optical wedge 11d111
d' moves downward (in the direction of the arrow B' force in the figure), and the balance of the light intensity of the light beam increases and decreases in the opposite direction.The change in the total light intensity due to photoelectric adjustment by this optical wedge is as shown in Figure 4. When one of the two color light beams reaches 100%, the total amount of light becomes the largest, but even if the balance of light amounts changes, the total amount of light does not change significantly.

In this way, the light beam 6B is a combination of two color light beams whose light quantity balance has been adjusted by the optical wedge member 11, and the beam splitter 10 divides the light beam into Ar+
After being split from the laser 2, the optical path is changed by the anti-mirror provided on the optical path, and together with the half mirror provided at a position to receive both lasers.
14 from two directions perpendicular to each other.

This half mirror 14 transmits the Ar+ laser 2A polarized horizontally to the optical path and reflects the optical beam 6B polarized vertically to the optical path.
Both light beams are combined on the same optical path. This combined light beam 8AB has two wavelengths, Ar+ laser and He-Ne laser, and has two polarization directions in the directions of arrows a and b. After this light beam 8AB enters and is reflected by a reflecting mirror 15 provided on the optical path,
The light enters a reflecting mirror 16 provided on the same plane, and then enters a reflecting mirror 17. The two wavelengths and polarization direction of the light aperture dome 8AB are maintained unchanged by reflection. Light reflected by reflector 17, beam 8AB
is incident on a beam splitter 18 similar to the beam splitter 10 stacked on the optical path, and a light beam having a polarization component perpendicular to the optical path before entering the beam splitter 18 is transmitted by this beam splitter 18. is,
A light beam with a polarization component horizontal to the optical path is reflected and split into two light beams again. The Ar+laser 2A' reflected by the beam splitter 18 is
The + laser 2A and the light beam 6B' transmitted through the beam splitter 18 are the same as the light beam 6B.

According to the device having the above-described optical system, by adjusting the optical wedge member 11, the light intensity balance of the Ar+ laser 2B and the He-Ne laser 4B can be changed, and a light beam formed by combining these two lasers can be obtained. If 6B', which is the same light beam as 6B, is used for image reading, a desirable reading scan will be performed, and as a result, desirable recording and reproduction will be possible. Note that in this example, Ar
+ Laser 2 is randomly polarized and He-Ne laser 4
B is linearly polarized in a direction perpendicular to the optical path, which is provided as close to the optical path as possible after the light beam 6B used for reading and recording color images and the Ar+ laser 2A are combined by a half mirror 14. This is to reduce costs by reducing the number of expensive optical elements by sharing optical elements to perform common optical processing and then splitting the beam into both beams by the beam splitter 18. When installing independent optical systems for each, Ar+laser, He
- It is not necessary for the Jle laser to have polarization characteristics as described above. Furthermore, in cases where simultaneous recording is not necessary (for example, displaying on a CRT, storing image information in memory and outputting it later, etc.), an optical element for obtaining a recording light beam is not required. There is also no need to consider the polarization characteristics of the laser. In this example, Ar+ laser (red) and @e-Ne laser (blue) were used as two color light beams, but the light beam is not limited to these two types of light beams, and two different color light beams are used. Any light beam can be used. Further, the number of light beams is not limited to two types, and light beams of three or more colors may be used.

For example, in the case of three colors, if three optical wedges with stepwise density changes arranged as shown in Figure 5 are linked in the same direction, changes in the total amount of light can be kept small and the difference between each light can be reduced. Balance can be adjusted. Alternatively, the light amount may be adjusted for two of the three colors. The optical wedge member is not limited to the one shown in FIG. 2, in which a pair of optical wedges with opposite concentrations do not move in the same direction at the same time, but also the rack 11A, as shown in FIG. 11
Two optical wedges 11 with B having the same density change direction
D111D' frame, and the pinion 11
Knob 1 that engages C and is coaxial with the binion 11C.
By turning 1E, the two optical wedges 11 [)
, 11[)' in the opposite direction to adjust the light amount. Further, the two optical wedges may be arranged separately on the optical path to be provided, and in that case, they can be interlocked by various interlocking mechanisms using links, wires, gears, etc.

Next, referring to FIG. 6, a color image scanning and reading apparatus according to the present invention will be described which is based on the optical system described with reference to FIG.

The Ar + laser 102 emitted from the light source 101 is randomly polarized, and the beam splitter 110 provided on the optical path converts the Ar + laser 102 into an Ar laser with a polarization direction horizontal to the optical path.
+ laser 102A and Ar + laser 102B having a polarization direction perpendicular to the optical path (direction indicated by the arrow in the figure), and this divided A r + laser 102B is also linearly polarized in the direction indicated by the arrow, and is emitted from the light source 103. It enters the optical wedge member 11 together with the emitted He-Ne laser 104B, and the amount of light is adjusted depending on the color document to be read.

After being adjusted, the light beams are combined on the same optical path by a half mirror 112 to become a light beam 106B.

On the other hand, the divided Ar+ laser 102A enters a modulator 200 provided on the optical path. This modulator 200 modulates the Ar+ laser 102A according to image information. The modulated A r + laser 102A enters the reflecting mirror 113 to change the optical path, and then the light beam 102A changes its optical path.
Together with 6B, the light enters the half mirror 114 from two directions and is combined on the same optical path. Combined light beam 108AB4
．． The light beam has the wavelengths of the "tAr" laser and the He-Ne laser, and has two polarization directions in the directions of arrows a and b, and the modulation by the modulator 200 is also maintained for the polarization component in the direction of arrow a. This light goal 10
After being reflected by reflecting mirrors 115 and 116, 8A8 is incident on a beam expander 201, where it is made into a light beam of an appropriate thickness. The light beam 108AB processed by the beam expander 201 enters the galvanometer mirror 117. The galvanometer mirror 117 is rotated or vibrated in the direction of arrow m by an electric signal, and the light beam 108AB is rotated from 108A8' to 108AB''.
Deflects in a fan-shaped range up to. In addition, light beam 108AB
The device for deflecting is not limited to a galvanometer mirror, but may be a polyhedral rotating mirror deflector. The light beam 108AB deflected by the galvanometer mirror 117 enters the lens system 202. This lens system 202 allows the deflected light beam to reach a flat reading surface 206 and a flat recording surface 206.
f to be able to scan at a constant speed on 4
It is a θ lens. The light beam 108AB that has passed through this lens system 202 is incident on the first beam splitter 118. The beam splitter 118 splits the light beam 108AB by reflecting a light beam having a polarization component in the direction of the arrow a and transmitting a light beam having a polarization component in the direction of the arrow. Assuming that the beam is the Ar+ laser 102A' and the transmitted light beam is the light beam 106B', the Ar+ laser 102A' corresponds to the Ar+ laser 102A, and the light beam 106B' corresponds to the light beam 106B. This Ar+ laser 102A' is a light beam modulated by the modulator 200, and the light beam 106B' is a light beam whose light quantity balance is adjusted by the optical wedge member 111. This Ar+ laser 102A' is reflected by a reflection mirror 203 to change its optical path, and then scans the recording surface 204 of the sensitive material moving in the direction of arrow A to record an image.

On the other hand, the light beam 106B' is transmitted to the beam splitter 118.
The scanning surface 206 is reflected by a half mirror 205 placed behind the scanning surface 206 and moves in the direction of arrow B. The light beam incident on the reading surface 206 is focused by an optical fiber 207 and guided to a light receiver 208. The receiver 208 generates a signal depending on the intensity of the light beam and controls the modulator 200 with this signal through an electrical circuit (not shown), thereby controlling the optical beam 10.
Modulate 2A. Further, the back of the light beam 106B', the light beam 106B'' that has passed through the half mirror 205 scans the grating 209, and is then guided to the light receiver 211 via the cylindrical lens 210.

The light receiver 211 generates a signal using the scanning light beam, and controls the light beam to uniformly scan the reading surface and the recording surface using this signal.

[Brief explanation of drawings]

FIG. 1 is a principle diagram of the optical system used in the color image scanning and reading device of the present invention, and FIGS. 2 and 3 are diagrams showing the first and second optical wedge members used in the color image scanning and reading device of the present invention. FIG. 4 is a graph showing the relationship between the balance of each light beam and the total amount of light used in the color image scanning/reading device of the present invention. FIG. An explanatory diagram illustrating the outline of the third embodiment, FIG. 6 is a color ii! of the present invention! FIG. 2 is a schematic diagram showing an embodiment of an image scanning reading device. 1.3 ... Light m 2 ・A r + laser 4 B −
He-N e L/ -+J"10.18... Beam splitter 11... Optical wedge member 12.14... Half mirror 13, 15, 16, 17... Reflector 1i111!1 Cabinet 4 figure Figure 5

Claims (1)

[Claims] A color image scanning/reading device configured to scan a color original carrying a color image with a light beam formed by combining light beams of at least two different colors to read image lines and obtain an image signal, Optical wedges are provided in the optical paths of the light beams of at least two colors among the light beams before combination, and these optical wedges are arranged such that the concentrations of the optical wedges for the light beams change in opposite directions. A color image scanning/reading device characterized by being provided with an interlocking mechanism.