JPH03143647A - image forming device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an image forming apparatus for recording color images using a color photosensitive sheet.

[Prior Art] In recent years, color image forming apparatuses (for example, Color Bunonta)
An apparatus has been proposed that exposes a photosensitive sheet to light using a single exposure light source to form a color image.

In other words, a photosensitive sheet with a mixture of multiple types of color-forming photosensitizers each having different photosensitive wavelength ranges is used, and a single exposure light source is used to simultaneously irradiate light including the photosensitive wavelength ranges of each photosensitive agent. The light from the light source is separated into each color, each color is individually intensity-modulated and combined, and the combined light beam is used to expose a photosensitive sheet.

In this type of image forming apparatus, as shown in FIG.
R), green (G), and blue (B) filters P4 are used to change the characteristics of light transmitted through the filters P4. The light transmitted through the filter P4 is reflected by the reflective surface of a rotating polygon mirror P5, and is then collected onto a photosensitive sheet P7 via a lens P6 to expose the photosensitive sheet P7.

[Problems to be Solved by the Invention] However, in the above image forming apparatus, the filter P4 and the rotating polygon mirror P5 are rotated in accurate synchronization with respect to the light beam using RGB time-division signals (image signals). It is difficult to precisely perform such synchronization control, and in some cases, synchronization may occur, making it impossible to form a good image.

An object of the present invention is to solve the above problems and provide an image forming apparatus that forms good images with a simple mechanism.

[Means for Solving the Problems] The image forming apparatus according to claim 1 of the present invention includes a photosensitive sheet on which a plurality of types of color-forming photosensitizers having different photosensitive wavelength ranges are mixed and supported on the surface of the photosensitive sheet. An image forming apparatus that exposes with light from a single exposure light source that simultaneously emits light in a photosensitive wavelength range, the image forming apparatus comprising: a modulator that modulates the intensity of the light that exposes the photosensitive sheet; and a photosensitive material of each of the photosensitive agents. The gist of the present invention is to include a rotating polygon mirror having a reflective surface that reflects light from the modulator for each wavelength range.

The image forming apparatus according to a second aspect of the present invention is characterized in that the rotating polyhedron according to the first aspect has reflective surfaces whose number is an integral multiple of the number of wavelength ranges to which the light is sensitive.

[Function] The image forming apparatus according to claim 1 of the present invention comprises a photosensitive sheet in which a plurality of types of color-forming photosensitizers having different photosensitive wavelength ranges are mixed and supported on the surface, and a light including the photosensitive wavelength ranges of each photosensitive agent. Using a single exposure light source that emits simultaneously, the photosensitive sheet is exposed to light by irradiating the photosensitive sheet with light from this exposure light 5 source.

In the exposure, first, light from a light source is guided to a modulator to modulate the intensity of the light that exposes the photosensitive sheet,
Next, the light E output from the modulator is reflected by the reflecting surface of the rotating polygon mirror. Here, each reflective surface of this rotating polygon mirror is
Since only the light corresponding to the sensitive wavelength range of each photosensitive agent is reflected, out of the light output from the modulator, only the light in the specific sensitive wavelength range is reflected to expose the photosensitive sheet.

In other words, rather than changing the characteristics of light with a filter, the characteristics of the light that exposes the photosensitive sheet can be changed using the reflection characteristics of the rotating polyhedron, which simplifies the overall mechanism of the device and enables the formation of good images. Become.

In the image forming apparatus according to a second aspect of the present invention, since the rotating polyhedron according to the above-mentioned claim has a reflective surface whose number is an integral multiple of the number of photosensitive wavelength ranges, control of the operation of the rotating polyhedron is simplified.

[Example] Hereinafter, a color printer, which is a preferred example of the present invention, will be described based on FIG. 1.

As shown in the figure] 2. The printer 1 of this embodiment is equipped with an exposure scanning section 2 and is a device that forms a color image using a photosensitive pressure sensitive sheet 3. This exposure scanning section 2 is equipped with a white light source 10.
Collimating lens 1] 9-color modulation section 20. The main components are a polygon mirror 12 and an fθ lens 13.

The light source 10 is red (R) and green (G).

A halogen lamp or a metal halide lamp that emits so-called white light containing a blue (B) color component can be used. For example, this metal halide lamp emits 400nm of visible light.
It is a light source with a spectral energy distribution that emits a luminous flux with a wavelength ranging from 700 nm to 700 nm.

The color modulation section 20 includes a color separation prism 211 and a reflection mirror 22.
．． 23. 24. 25. It is composed of a color combining prism 27 and light intensity modulators 27R, 27G, and 27B (hereinafter collectively referred to as modulators 27).

Among these, the color separation prism 21 is a prism with a reflective film provided on its cemented surface, and this reflective film reflects or transmits white light for each color to separate optical paths. Here, the color separation prism 21 reflects, for example, red light to the left, and the reflection mirror 22 guides the reflected light to the red modulator 27R. Similarly, the blue light is reflected to the right, and the reflected light is guided by the reflecting mirror 23 to the blue modulator 27B. Furthermore, this color separation prism 21 transmits green light and guides the transmitted light to a green modulator 27G.

The spectral reflectance of the reflective film of the color separation prism 2 is shown in FIG. Here, FIG. 2(a) shows the characteristics of a reflective film that selectively reflects red light and guides the optical path to the left in FIG. 1. Similarly, FIG. 2(c) shows the characteristics of a reflective film that selectively reflects blue light and guides the optical path to the right in FIG. Incidentally, the remaining green color is transmitted as a result, but as another example, when selectively reflecting the green color, a reflective film having the characteristics shown in FIG. 2(b) is used.

Further, as the modulator 27, for example, PLZT using an electro-optic effect is used, and modulators 27R227B, 27 of each color are used.
Gl thus modulates the light intensity based on modulation signals corresponding to red, blue, and green components, respectively.

The reflecting mirrors 24 and 25 reflect the respective color lights from the modulators 27R and 27B and guide them to the color combining prism 26.

The color synthesis prism 26 is used in reverse of the color separation prism 21, and the reflective film provided on its joint surface has the same characteristics as the color separation prism 21, and allows reflection or reflection for each color. The transmitted light is combined into a single optical path and becomes white light again.

The photosensitive pressure-sensitive sheet 3 is similar to the photosensitive sheet known from Japanese Patent Laid-Open No. 58-88739 or Japanese Patent Laid-Open No. 58-88740.

For example, yellow (Y), magenta (M), cyan (C)
Three types of microcapsules are used, each containing a dye precursor for each color and a photocurable resin that is sensitive to light in a specific wavelength range, separately encapsulated in an outer shell that collapses when pressure exceeds a certain value. be done. In other words, a photosensitive sheet coated with these microcapsules and a separate color developing sheet coated with color developer particles that cause a color reaction with each dye precursor (so-called separate type photosensitive pressure sensitive sheet) are used. It is possible to adopt a method in which both sheets are overlapped and developed under pressure.

FIG. 3 shows the spectral sensitivity characteristics of the photosensitive pressure sensitive sheet 3 in this example, with blue around 450 nm and green around 5 nm.
It has a peak sensitivity around 50 nm and a red color around 650 nm.

Next, the polygon mirror 12, which is the main part of this embodiment, will be explained.

The polygon mirror 12 has six reflective surfaces 15R, 1 on its surface.
It is a regular hexagonal prism member having 5G and 15B (hereinafter collectively referred to as reflective surfaces 15), and rotates at a constant angular velocity in the direction of arrow A (FIG. 1).

The reflective surfaces 15 are configured such that a pair of parallel surfaces reflect only red, green, and blue, respectively. That is, each reflective surface 15
A reflective film having the same function as the reflective film provided on the color separation prism 21, etc. described above is formed.As a result, a reflective surface 15R that reflects only red light, a reflective surface 15G that reflects only green light, and a reflective surface 15G that reflects only blue light are formed. Reflective surfaces 15B are arranged in order on the surface of the polygon mirror 12.

When the light guided from the light modulation unit 20 to the polygon mirror 12 is for a red component, this polygon mirror 12 has a 15-square reflective surface that reflects only red light, and is arranged at a position where the light is reflected (reflection position). It is controlled based on a synchronization signal (image signal) so that the Similarly, if the light is for the green component, the reflective surface 15G that reflects only the green color is placed at the reflecting position, and if the light is for the blue component, the reflective surface 15B that reflects only the blue color is placed at the reflective position. be done.

Next, the operation of the printer 1 performed by driving the polygon mirror 12 and the like will be explained.

First, the light emitted from the light source 10 that emits white light (the light is focused approximately parallel by the collimating lens 11 and sent to the color modulation section 2).
0 is introduced. The light introduced into the color modulation unit 20 becomes white light that is modulated into green and blue color components through the prisms 21 and 26, the mirrors 22 to 25, and the modulator 27, and is transmitted to the polygon mirror 12. be guided.

This polygon mirror 12 is connected to the color modulation section 2 as described above.
It corresponds to white light modulated by 0 and rotates under control based on a synchronization signal. In other words, the tags are arranged so that the predetermined reflecting surfaces 5 rotate according to the modulation of the white light and come to the reflecting position.As a result, only a specific color among red, green, and blue is reflected, and is reflected by each reflecting surface 15. The light is deflected within a constant angular velocity range and guided to the reflective tag fθ lens 13. This child θ lens 13 converges the parallel light beam deflected at a constant angular velocity onto a minute spot moving at a constant linear velocity on the photosensitive pressure-sensitive sheet 3, whereby a color image is exposed. The color image is then developed and fixed by a developing (& fixing device, not shown) to complete a color image.

Such a configuration and operation produces the following effects.

That is, in the printer 1 of this embodiment, only the polygon mirror 12 is mechanically driven in synchronization with the image signal instructing the modulation of light, and the structure is extremely simple. This has the advantage of facilitating manufacturing and maintenance. The simple structure has the effect of reducing synchronization errors during image formation. Further, since there is no need to use a filter as in the conventional method, there is no need to consider the flatness, thickness, and transmittance of the filter, and there is an advantage that precise image formation can be performed.

Although the embodiments of the present invention have been described above, the present invention is not limited to these embodiments in any way, and it goes without saying that it can be implemented in various forms without departing from the gist of the present invention.

For example, although the polygon mirror 12 of this embodiment has a hexagonal shape, it may be provided with an even or odd number of reflecting surfaces 15 other than that.

Further, it is preferable that the reflective surface 15 is formed to be an integral multiple of the number of wavelength ranges to which the photosensitive agent is sensitive, since this simplifies the control of the polygon mirror 12 based on image signals.

Further, the modulator 27 is not limited to an electro-optic modulator, but may include an acousto-optic modulator, a liquid crystal shutter, and other structures having equivalent effects.

In addition, the light source] is adjusted to match the sensitivity of the photosensitive pressure sensitive sheet 3.
A fixed filter may be provided between O and the photosensitive pressure sensitive sheet 3.

Further, the reflectance of the reflective surface 5 of the polygon mirror 12 is not the same, and may be changed depending on the color reflected.

[Effects of the Invention] As described in detail above, the image forming apparatus according to claim 1 of the present invention modulates the intensity of light that exposes the photosensitive sheet using the modulator, and also modulates the intensity of the light that exposes the photosensitive sheet using the reflective surface of the rotating polygon mirror. Since the light from the modulator is reflected for each sensitive wavelength range, filters and the like can be omitted and the device configuration can be simplified. This facilitates manufacturing and maintenance. Further, since synchronization control of filters, etc. is not necessary, synchronization deviations are less likely to occur, and a high-quality image can be formed.

Further, the image forming apparatus according to the second aspect of the present invention has the advantage that the rotating polyhedron has reflective surfaces having a number of integral multiples of the number of photosensitive wavelength ranges, so that synchronization control of the rotating polyhedron becomes easy.

[Brief explanation of the drawing]

FIG. 1 is a schematic configuration diagram showing a printer according to an embodiment of the present invention;
FIG. 2 is a characteristic diagram showing the spectral reflectance of a color separation prism, FIG. 3 is a characteristic diagram showing the composite sensitivity of a photosensitive sheet, and FIG. 4 is a configuration diagram showing a conventional printer. 1... Printer 3... Photosensitive pressure sensitive sheet] 0... Light; Original 12... Polygon mirror 15.15R, 15G. 20... Color modulation section 27.27R, 27G. 5B...Reflecting surface 27B...Modulator

Claims (1)

[Scope of Claims] 1. A photosensitive sheet in which a plurality of types of color-forming photosensitizers having different photosensitive wavelength ranges are mixed and supported on the surface is used for single exposure in which light including the photosensitive wavelength ranges of each of the photosensitive agents is emitted simultaneously. An image forming apparatus that exposes with light from a light source, comprising: a modulator that modulates the intensity of the light that exposes the photosensitive sheet; and a reflector that reflects the light from the modulator for each sensitive wavelength range of each of the photosensitizers. An image forming apparatus comprising: a rotating polygon mirror having a surface. 2. An image forming apparatus, wherein the rotating polyhedron according to claim 1 has reflective surfaces whose number is an integral multiple of the number of photosensitive wavelength ranges.