JPH0729450B2 - Color image output device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Use] The present invention is designed to scan a corresponding photoconductor by reflecting a laser beam respectively modulated according to a plurality of color image signals by a single deflecting mirror means. The present invention relates to a color image output device.

[Conventional technology]

As a conventional color image output device, for example, a color including a rotating polygon mirror that modulates laser light output from a laser light source according to a color image signal, and scans and exposes a photoconductor with the modulated laser light. There is an image output device.
The number of sets of laser light sources, modulators, rotating polygon mirrors, photoconductors, etc. are provided according to the number of colors, and the electrostatic latent image of the photoconductor formed by the above-mentioned exposure is developed with the corresponding color toner. After that, by transferring the toner images of a plurality of colors in an overlapping manner, a full-color image can be reproduced. Of course, instead of a full-color image,
It is also possible to copy multicolor images.

[Problems to be solved by the invention]

However, according to the conventional color electronic copying machine, the number of sets of rotating polygon mirrors corresponding to the number of colors is provided, and
Since it rotates at high speed, cost reduction, low power consumption,
There is a limit in extending the life, and when each mirror surface has a tilt or a difference in reflectance, there is a problem that the image quality becomes non-uniform.

[Means for solving problems]

The present invention has been made in view of the above, and in order to achieve downsizing, cost reduction, low power consumption, long life, and uniform image quality, different polarizations modulated by different color signals on a common optical axis are provided. Optical signal output means for outputting different color optical signals having a wavefront, a scanner mirror for deflecting and scanning different color optical signals on a common optical axis, and different color optical signals deflected and scanned by the scanner mirror for different polarization planes. Separating means for separating in accordance with the different photoconductors that are exposed by different color light signals separated by the separating means to form electrostatic latent images of different colors; The present invention provides a color image output device having recording means for recording a color image on a recording paper.

Hereinafter, the color image output device of the present invention will be described in detail.

〔Example〕

1 to 3 show a first embodiment of the present invention. First, the scanner unit 11 will be described with reference to FIGS. The scanner unit 11 has a laser light source 1a, 1b, 2a, 2b provided on a base 11A. This laser light source
1a, 1b, 2a and 2b emit laser lights 3a, 3b, 4a and 4b which are modulated according to color signals of black (BL), yellow (Y), magenta (M) and cyan (C), for example. (It does not matter whether it emits only a modulated laser beam or an external modulation method having an external modulator). Polarizing beam splitters (hereinafter referred to as "PBS") 5a, 5 are placed on the optical axes of the laser beams 3a, 3b.
b is provided, and a reflection mirror 7 for making the laser beams 4a and 4b incident on the PBSs 5a and 5b on the optical axes of the laser beams 4a and 4b.
a and 7b are provided. Reflecting mirrors 7a, 7b and PBS 5a, 5b
Half-wave plates 6a and 6b are provided between them, and the scanner body 9 is supported so as to rotate by a predetermined angle on the optical axes of the laser beams 3a, 3b, 4a and 4b emitted from the PBSs 5a and 5b. A double-sided reflective scanner mirror 8 is provided. Laser light 3a, 3b, 4 reflected by the scanner mirror 8
Scanner lenses (f arc sin θ lenses) 10a and 10b are provided on the optical axes of a and 4b.

FIG. 3 shows a color image output device having this scanner unit 11, and laser light emitted from the scanner unit 11
The PBS 12a is provided on the optical axes of a and 4a, and the PBS 12b is provided on the optical axes of the laser beams 3b and 4b. Reflection mirrors 13a and 13b are provided on the transmission optical axes of the PBSs 12a and 12b, and reflection mirrors 14a and 14b are provided on the reflection optical axes thereof. The photosensitive drum 15, on the reflection optical axis of the reflection mirrors 13a, 13b, 14a, 14b,
16, 17, 18 are provided. Photosensitive drum 15, 16, 17,
Reference numeral 18 is developed with developing toners of black, yellow, magenta, and cyan, and transfers the toner image onto the recording paper conveyed through the transfer passages 30 (note that the trivial portion such as the fixing portion is omitted). .

In the above configuration, from the laser light source 1a, 1b, 2a, 2b
When laser light 3a, 3b, 4a, 4b (polarization plane of P wave with respect to PBS 5a, 5b) modulated according to BL, Y, M, C color signals is emitted, the laser light 3a, 3b becomes PBS 5a, 5b
The laser beams 4a and 4b are reflected by the reflection mirrors 7a and 7b, converted into S waves by the half-wave plates 6a and 6b, and incident on the PBSs 5a and 5b. That is, the laser beams 4a and 4b and the laser beams 3a and 3b are superposed on the same optical axis by the PBSs 5a and 5b, and then reach the scanner mirror 8 and are reciprocally moved at a predetermined angle in the main scanning direction. To be scanned.

Of the laser light 3a, 3b, 4a, 4b reflected by both surfaces of the scanner mirror 8, the laser light 3a, 3b is PBS 12a, 12b.
After passing through b, the light is reflected by the reflection mirrors 13a and 13b to irradiate the photosensitive drums 15 and 18, and electrostatic latent images corresponding to black and yellow color signals are formed thereon. Also laser light
After being reflected by the PBSs 12a and 12b, the beams 4a and 4b are reflected by the reflection mirrors 14a and 14b and irradiate the photosensitive drums 16 and 17, and electrostatic latent images corresponding to magenta and cyan color signals are formed thereon. After that, the electrostatic latent images on the photosensitive drums 15, 16, 17, and 18 are developed with black, yellow, magenta, and cyan toners, and transferred onto the recording paper conveyed through the conveying passage 30 so that the black print portion is black. A full-color image recorded with toner is reproduced.

Here, the screen scanner mirror 8 may be replaced with two single-sided scanner mirrors.
It is also possible to perform multicolor recording of three colors. In case of two colors, if the laser light sources 2a and 2b are omitted, PBS5a and PBS5
Of course, the b, half-wave plates 6a, 6b are not necessary, and if the laser light sources 1b, 2b are omitted, the scanner mirror 8 can be replaced with a single-sided mirror.

4 and 5 show a second embodiment of the present invention, in which the laser beams 3a and 4 emitted from the PBSs 5a and 5b of the scanner section 11 are shown.
The optical axes of b and 3b and 4b are shifted so that the PBSs 12a and 12b shown in FIG.
It can be replaced with a, 19b. That is, the laser light 3a,
3b is directly incident on the reflection mirror 13a, 13b, laser light 4a,
4b is incident on the reflection mirrors 19a and 19b. Since the other operations are the same as those in the first embodiment, the description will be omitted.

FIG. 6 shows a third embodiment of the present invention, which corresponds to the first embodiment.
PBS 5a, 5b, half wave plates 6a, 6b are omitted, and the reflection mirror 20
It is replaced with a and 20b. Other explanations are omitted because they are self-explanatory.

In the first and second embodiments, the half wave plates 6a, 6
b may be placed on the light source side of the reflection mirrors 7a and 7b. Also,
In each embodiment, the scanning lenses 10a and 10b have the f arc sin θ
Since it has the characteristics, the moving speed of the laser light on the photosensitive drums 15 to 18 is kept constant. On the other hand, the photosensitive drums 15 and 1
In 6, 17 and 18, the scanning direction of the laser light is reversed, but this can be solved by reversing the arrangement of the image data or shifting the writing timing in the reciprocal scanning by half a cycle. Furthermore, the scanning lenses 10a and 10b described above
Since it is sufficient to use only two in the case of two colors and two colors, the deviation of the scanning position of the photosensitive drum due to the individual difference of the lens is eliminated, and the color deviation due to the difference in image height can be prevented. Further, since the unidirectional rotary scanning by the rotary polygon mirror is replaced by the reciprocal scanning of the single-sided mirror, the writing speed is doubled because the image is written on both the forward and backward paths.

〔The invention's effect〕

As described above, according to the color image output device of the present invention, an optical signal output unit that outputs different color optical signals having different polarization planes modulated by different color signals on a common optical axis, and different color light output units. By a scanner mirror that deflects and scans signals on a common optical axis, a separation unit that separates different color optical signals that are deflected and scanned by the scanner mirror according to different polarization planes, and different color optical signals that are separated by the separation unit. It has a different photoconductor that is exposed to form an electrostatic latent image of a different color, and a recording unit that records a color image on a recording paper based on the electrostatic latent image of a different color of the photoconductor. In addition, cost reduction, low power consumption, long life, and uniform image quality can be achieved. The scanner unit can be reduced to 1/4 in size, and the power consumption is about 1/1000 compared to the case of using four rotating polygon mirrors. Since there is no part, the life is long, and since scanning is performed with a single mirror surface, it is possible to prevent errors in the scanning position due to surface tilt like a rotating polygon mirror and non-uniformity of the image due to the difference in reflectance between each surface. Since it is not necessary to perform high-precision machining required between the surfaces of the polygon mirror, it is possible to reduce the number of parts and the cost.

[Brief description of drawings]

1 to 3 show a first embodiment of the present invention.
The scanner part of the figure is a plan view, FIG. 2 is a side view of the scanner, and FIG. 4 and 5 show a second embodiment of the present invention, FIG. 4 is a side view of the scanner portion, and FIG. 5 is an overall explanatory view. FIG. 6 is a side view of the scanner section showing the third embodiment of the present invention. Explanation of symbols 1a, 1b, 2a, 2b …… Laser light source 3a, 3b, 4a, 4b …… Laser light 5a, 5b …… Polarizing beam splitter 6a, 6b …… 1/2 wave plate 7a, 7b …… Reflecting mirror 8 ... Scanner mirror 9 ... Scanner body 10a, 10b ... Scanner lens 11 ... Scanner section 12a, 12b ... Polarizing beam splitter 13a, 13b, 14a, 14b ... Reflecting mirror 15, 16, 17, 18 ... Photosensitive drum

Claims (3)

[Claims] 1. An optical signal output means for outputting different color optical signals having different polarization planes modulated by different color image signals on a common optical axis, and deflecting the different color optical signals on the common optical axis. A scanner mirror for scanning, a separating means for separating the different color optical signals deflected and scanned by the scanner mirror according to the different polarization planes, and different colors exposed by the different color optical signals separated by the separating means. Color image output device comprising different photoconductors for forming the electrostatic latent images of 1. and recording means for recording a color image on a recording paper based on the different color electrostatic latent images of the photoconductors. . 2. A plurality of laser beams respectively modulated according to a plurality of color image signals are applied to the corresponding photoconductors to be exposed, and a color image is formed based on the electrostatic latent image formed by this exposure. In a color image output device for reproducing, a first laser light source that outputs a first optical signal having a first polarization plane that is modulated by a first color signal, and the first laser light source that is modulated by a second color signal. A second laser light source that outputs a second optical signal having a first polarization plane; and a first polarization plane of the second optical signal that is a second polarization plane orthogonal to the first polarization plane. Polarization plane conversion means for converting the first optical signal having the first polarization plane and passing the first optical signal and reflecting the second optical signal having the second polarization plane have different polarization planes. The first and second optical signals A first polarization beam splitter which is incident on the scanner mirror with the same optical axis, and the first and second optical signals having different polarization planes reflected by the scanner mirror are separated and applied to the corresponding photoconductors. A color image output device comprising a second polarization beam splitter. 3. An electrostatic latent image formed by irradiating a corresponding photosensitive member with a plurality of first to fourth laser beams respectively modulated in accordance with a plurality of color image signals and exposing the photosensitive member. In a color image output device for reproducing a color image based on the first and third optical signals, the first and third optical signals having the first polarization planes modulated by the first and third color signals are output. A laser light source and the first modulated by the second and fourth color signals
A second optical signal outputting second and fourth optical signals having different polarization planes
And a fourth laser light source, a polarization plane conversion means for converting the first polarization plane of the second and fourth optical signals into a second polarization plane orthogonal to the first polarization plane, and The first and third optical signals having one polarization plane are passed, and the second and fourth optical planes having the second polarization plane are transmitted.
A first and a second polarization beam splitter for causing the first and second, the third and the fourth optical signals having different polarization planes to be incident on the scanner mirror at the same optical axis by reflecting the optical signal of From the third and fourth polarization beam splitters for respectively separating the first and second, the third and fourth optical signals having different polarization planes reflected by the scanner mirror and irradiating the corresponding photoconductors A color image output device characterized by being configured.