JPH0414792B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to an image forming apparatus such as a color copying machine that obtains a color image by electrophotography using light-transmitting particles having a spectroscopic function.

Configurations of Conventional Examples and Problems Therein An image forming apparatus using light-transmitting particles having a spectroscopic function to which the present invention is applied includes, for example, a step of uniformly charging an electrophotographic photoreceptor; A process of uniformly and evenly electrostatically depositing a mixture of three types of light-transmitting particles that transmit only green and blue light, a process of exposing an optical image of a document onto a photoreceptor through the particles, and a process of photosensitive. The process of removing particles whose electrostatic adhesion with the body has been weakened or removed from the photoreceptor and forming a particle image on the photoreceptor, and heating the particles remaining on the photoreceptor to create images corresponding to red, green, and blue. There is a color copying machine that includes a step of sublimating and transferring cyan, magenta, and yellow sublimable dyes contained in particles to an image receptor.

In this type of color copying machine, the particles have a spectral function and a color development function that corresponds to the spectral spectrum, so it is possible to obtain a color image with a single image exposure and development process (hereinafter referred to as the one-shot method). ).

Conventionally, in general color copying machines, to adjust the hue of the resulting color image, filters with various transmission spectra are prepared between the original and the image forming area on the photoreceptor surface, and these are replaced during image exposure. I was going there depending on the situation. Adjusting the color tone using these filters requires complicated equipment configuration for filter replacement, loss of light amount due to the filter and resulting reduction in copying speed, high cost of the equipment due to the use of expensive filters, and only step-by-step adjustment. There were various drawbacks such as the inability to do so.

In addition, in an apparatus that uses a filter and color toner to repeat the exposure and development process three or four times and superimpose them on an image receptor to obtain a color image (hereinafter referred to as the three-shot method), during image exposure, By changing the illuminance of the document surface for each exposure, or by changing the developing power of the developing device for each development,
A method of adjusting the hue of a color image when one color or four colors are superimposed has been used.

However, in the one-shot type apparatus as in the above example, it is not possible to apply a method of adjusting the hue by changing the developing power or document surface illuminance for each color. Therefore, in the conventional one-shot system, it has been necessary to adjust the hue by replacing the filter.

OBJECTS OF THE INVENTION It is an object of the present invention to provide an image forming apparatus that overcomes the various drawbacks of the tint adjustment by replacing filters as described above and is equipped with a tint adjustment mechanism that can also be applied to a one-shot system.

Structure of the Invention The image forming apparatus of the present invention includes a scattering device that scatters light-transmitting particles having a spectral function onto a charged electrophotographic photoreceptor, an exposure device that image-wise exposes the particle surface of the photoreceptor after being sprayed, and Equipped with a developing device that selectively removes particles after exposure depending on the amount of transmitted light, and a light source with a constant spectrum and adjustable light amount between the scattering process and the developing process to uniformly remove particles from the particle surface of the photoreceptor. The apparatus is equipped with a color adjustment device that irradiates a light source, and is configured so that the tone of the copied image obtained can be adjusted by adjusting the amount of light from this light source.

DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments of the present invention will be described based on the drawings.

FIG. 1 shows the configuration of the main parts of a color copying machine using a one-shot method according to an embodiment of the present invention. 1 is a photoreceptor drum, which is attached to the outer circumferential surface of the metal drum.
Electrophotographic photoreceptor such as ZnO is coated. 2
A charger uniformly charges the surface of the photosensitive drum 1 as it rotates. Reference numeral 3 denotes a scattering device, which stores particles therein, and disperses the particles 4 uniformly and evenly onto the charged photoconductor, causing them to adhere to the photoconductor by electrostatic force. Reference numeral 5 denotes a main light source for performing imagewise exposure on the photosensitive drum 1, and irradiates the original 7 placed on the original platen 6. The reflected light from the original 7 is reflected by a mirror 8 and passes through a lens 9 to a mirror 10.
The particles 4 on the photoreceptor drum 1 are reflected again by
form an image on the surface of

Particle 4 is a mixture of three types of light-transmitting particles that transmit only red, green, and blue light, and only the part of the photoreceptor under the particles that transmits a large amount of light depending on the color of the pixel of the optical image. charge is removed. For example, in the red part of the optical image, the charge under the red particle is removed, and the charge under the green and blue particles, which do not transmit red, remains.

The photosensitive drum 1 and the particles 4 on its surface are uniformly exposed by a light source 13 of a color adjusting device 11 as the drum 1 rotates, and then reach a developing device 12 . In the developing device 12, only particles whose electrostatic adhesion to the photoreceptor has been removed or weakened are removed by image exposure or uniform exposure by the light source 13, and a color-separated image remains on the photoreceptor. The image on the photoreceptor is then transferred to a receiver paper and heat is applied to transfer the heat sublimable dye contained in the particles to the receiver paper (not shown). At this time, each of the red, green, and blue particles contains sublimable dyes of cyan, magenta, and yellow, which are complementary colors, so for example, in the red part of the light source, only the red particles are removed by the developing device 12. The green and blue particles produce magenta and yellow colors, reproducing red.

The above is a description of the main parts of the color copying machine to which the present invention is applied. Next, the operation of the color adjustment device 11 will be described in detail.

The color adjustment device 11 includes a light source 13 and its power supply source 1
4 and a light amount adjuster 15 that adjusts the input supplied to the light source 13. Main light source 5 for image exposure
The emission spectrum includes energy of all wavelengths of visible light almost equally, so that the optical image formed on the particle surface on the photoreceptor drum 1 is a standard color image. On the other hand, the light source 13 has an emission spectrum mainly consisting of red components around a wavelength of 650 nm, as shown at 17 in FIG. Light amount adjuster 1
The knob 16 at 5 can be operated from the outside of the apparatus, that is, at the 0 position at 16, the output of the light source 13 is zero, and the particle surface on the photoreceptor drum 1 is exposed to a standard color image. It reaches the developing device 12 with only one. As the knob 16 is turned toward the R side, the amount of light from the light source 13 increases, and in addition to exposing the standard color image on the particle surface of the photosensitive drum 1,
Red light is irradiated with an amount of light corresponding to the position of 6.
Therefore, of the particles on the photosensitive drum, a large proportion of the red particles are removed by the developing device 12 as a whole, and the color copy image obtained through the subsequent steps differs from the setting position of the knob 16 with respect to the standard tone. Depending on the color, the image will have a lot of red.

The above is the structure and operation of a color copying machine according to an embodiment of the present invention. Next, another embodiment will be described with reference to FIGS. 3 and 4. In Figure 3, 1 to 10, 1
2 shows the same content as in FIG. Color adjustment device 18
consists of light sources 19 and 20, a power supply source 21, and a light amount adjuster 22. The light source 19 is a light source having an emission spectrum with red as the main component, similar to that shown in FIG. It is a light source with Light amount adjuster 22
adjusts the input supplied to each of the light sources 19 and 20, and when the knob 23 of the light amount adjuster 22 is at the center position, the outputs of the light sources 19 and 20 are both zero, and the resulting image has a standard color tone. . knob 2
3 toward the R side, the amount of light from the light source 19 increases, and the color copy image obtained in the same manner as above becomes an image with a strong reddish tinge. Conversely, as the knob 23 is turned toward the B side, an image with a stronger bluish tinge is obtained.

FIG. 5 again shows a part of a color copying machine according to another embodiment. In the figure, 1 to 4, 6 to 10, and 12 indicate the same contents as in FIG. The color adjustment device 25 includes a main light source 26 for image exposure, a power supply source 29 for the light sources 27 and 28, a light amount adjuster 30 for adjusting the input to each light source, and the light sources 27 and 28. The emission spectra of the light sources 27 and 28 are respectively
This is similar to that shown in FIGS. The outputs of the light sources 27 and 28 corresponding to the position of the knob 31 are the same as in the embodiment shown in FIG. The amount of light from the main light source decreases as you turn it toward the side. As described above, in this embodiment, the color tone is adjusted by the irradiation by the light sources 27 and 28, and the light intensity of the main light source 26 is adjusted to prevent the entire image from becoming too bright due to the large number of particles being removed. This can be automatically prevented by interlocking adjustments.

Effects of the Invention The present invention as described above makes it possible to adjust the tone of a copied image without using a filter and with a simple configuration, and provides the following great effects.

(1) Compared to the method of replacing filters, the color tone can be adjusted with a much simpler configuration.

(2) Since there is no loss of light intensity due to color adjustment, the copying speed can be faster compared to methods using filters.

(3) In contrast to filter-based adjustment, which is a gradual adjustment determined by the type of filter used,
Continuous and minute adjustments are possible.

(4) The method of changing the developing power and document surface illuminance each time can only be applied to the three-shot method, but can also be applied to the one-shot method.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of a color copying machine according to one embodiment of the present invention, FIG. 2 is a diagram showing the emission spectrum of the light source used therein, and FIG. 3 is a diagram showing the configuration of a color copying machine according to another embodiment. FIG. 4 is a diagram showing the emission spectrum of another light source used therein, and FIG. 5 is a diagram showing the configuration of a color copying machine according to another embodiment. 1... Photoreceptor drum, 3... Spreading device, 4...
Particle, 5, 26... Main light source, 9... Lens, 1
1, 18, 25... Color adjustment device, 12... Developing device, 13, 19, 20, 27, 28... Light source, 1
5, 22, 30...Light amount adjuster.

Claims (1)

[Scope of Claims] 1. A scattering device that scatters light-transmitting particles having a spectroscopic function onto a charged electrophotographic photoreceptor, an exposure device that image-wise exposes the particles from the particle surface of the photoreceptor, and a device that transmits the particles after image exposure. A color adjustment device that is equipped with a developing device that selectively removes light depending on the amount of light, and that irradiates light from the particle surface of the photoreceptor with a light source that has a constant spectrum and can adjust the amount of light between the spraying step and the developing step. An image forming apparatus equipped with. 2. The image forming apparatus according to claim 1, wherein the light source is made up of a plurality of light sources having different spectra, and the amount of light of each light source can be adjusted. 3. The image forming apparatus according to claim 1 or 2, wherein the light intensity of the main light source of the exposure device that performs image exposure and the light intensity of the light source of the color adjustment device can be adjusted in conjunction with each other.