JPH0396073A - color image forming device - Google Patents

Abstract

PURPOSE:To perform print recording with a sharp contour by irradiating the plane of a photosensitive recording medium with wavelength light fitted in each photosensitive wavelength area of the photosensitive recording medium by making incident an accelerated secondary electron. CONSTITUTION:When a thermoelectron is emitted with a heating means 110 based on color image information, a secondary electron is emitted from the thermoelectron with an electron multiplying means 103, and after the number of secondary electrons is increased, the electronic speed of the secondary electron is accelerated, and it is made incident on the plane of a fluorescent element 114 that is a fluorescent means. On the plane of the fluorescent element 114, a fluorescent material, for example, the one emitting red light for the image information of red color, the one emitting green light for the image information of green color and the one emitting blue light for the image information of blue color are applied, respectively, and the fluorescent element 114 emits light with the incidental energy of the secondary electron, and the plane of the photosensitive recording medium 204 is irradiated with the light, then, the color image information is exposed and recorded on the plane of the medium 204.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a color image forming apparatus that records color image information on the surface of a photosensitive recording medium having a plurality of photosensitive wavelength ranges for producing a color image.

[Prior Art and Problem 8] In recent years, various color image forming apparatuses have been known that record color image information on the surface of a photosensitive recording medium compatible with color images. In particular, with the progress of digitalization of image information, devices using semiconductor lasers, light emitting diodes (LEDs), and the like as information light have also been put into practical use.

By the way, currently the semiconductor laser is 780 to 830
It can only be put to practical use in a specific wavelength range, such as 1550 nm (CD players, laser printers, etc.) or 1550 nm (general communications, etc.). In addition, the practical wavelength range of LED is 650
The wavelength range that can be put to practical use is also limited, such as 840 nm, 750 nm, or 840 nm. Therefore, in order to record color image information on a photosensitive recording medium using information light in these wavelength ranges, it is necessary to develop materials for the recording medium that have photosensitivity suitable for these wavelength ranges.

However, for example, some photosensitive recording media such as silver halide photographic films and photosensitive microcapsule sheets (see JP-A-58-8873-9, U.S. Pat. No. 4,399,209, etc.) contain the semiconductors mentioned above. There are some products whose photosensitivity does not match that of lasers, etc. For example, in the case of a silver halide photographic film, its spectral sensitivity is in the short wavelength region of 400 to 700 nm, so the above-mentioned semiconductor laser etc. cannot be used as it is. There are also special silver halide photographic films that have sensitivity in the infrared region (such as those made by Kodak), but these films have lower sensitivity in the infrared region than in the shorter wavelength region, so they cannot be exposed to light. A large amount of light is required, resulting in high energy costs. Furthermore, the photosensitive microcapsule sheet described above also has spectral sensitivity in the short wavelength range of 400 to 7000 m, so that a semiconductor laser cannot be used. Even if semiconductor lasers were to be developed that could be used in photosensitive recording media having spectral sensitivity in these specific wavelength regions, there were problems such as high energy costs due to the short wavelengths.

On the other hand, there is also a device that records images by using a cathode ray tube (CRT) as information light.
By coating the RT surface with a fluorescent substance that emits light of a wavelength that matches the spectral sensitivity of the photosensitive recording medium, matching of the information light and the sensitive wavelength distribution of the photosensitive recording medium can be easily achieved. However, according to this method, when the electron beam output is increased, it is difficult to narrow down the beam spot diameter, and therefore it is difficult to obtain high brightness, and there are quality problems such as unclear printing outlines.

The present invention has been made in order to solve the above-mentioned problems, and is a color image capable of recording color images at high output on a photosensitive recording medium surface having a plurality of unique wavelength ranges for producing color images. A forming device is provided.

As a result, color image quality can be maintained and improved, and at the same time, energy costs for recording information can be reduced and the apparatus can be made more compact.

[Means for Solving the Problems] In order to achieve this object, the color image forming apparatus of the present invention exposes the surface of a photosensitive recording medium having a plurality of sensitive wavelength ranges to light based on color image information in order to form a color image. a heating means for emitting thermoelectrons based on the color image information; and electrons for emitting secondary electrons and multiplying the number of secondary electrons by the electron energy of the thermoelectrons emitted by the heating means. a multiplier; a secondary electron acceleration means for accelerating the secondary electrons multiplied by the electron multiplier;
a fluorescent means for emitting light having a wavelength matching each of the photosensitive wavelength ranges of the photosensitive recording medium upon incidence of secondary electrons accelerated by the secondary electron accelerating means, and the wavelength destination of the light emitted by the fluorescent means is The structure is such that the light is irradiated onto the surface of the photosensitive recording medium.

[Function] According to the color image forming apparatus of the present invention having the above configuration, when thermoelectrons are emitted by the heat generating means based on color image information, the thermoelectrons are converted into secondary electrons by the electron multiplier. After the number of secondary electrons is multiplied, the electron speed of the secondary electrons is accelerated by the secondary electron accelerating means, and the secondary electrons are incident on the surface of the fluorescent element, which is the fluorescent means. On this fluorescent element surface, there are a plurality of types of fluorescent substances having spectral sensitivity characteristics corresponding to each of the sensitive wavelength ranges of the photosensitive recording medium, for example, a fluorescent substance that emits red light for red image information, A fluorescent substance that emits green light is coated for green image information, and a fluorescent substance that emits blue light is coated for blue image information, and the fluorescent element is coated with a fluorescent substance that emits blue light. By emitting light due to the incident energy, the light is irradiated onto the surface of the photosensitive recording medium, and color image information is exposed and recorded on the surface of the medium.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a schematic configuration of this device. As shown in the figure, in this apparatus, an optical scanner 100 is arranged to face the surface of a photosensitive recording medium 204 via an optical lens 203, and a scanner driver 2 for driving the optical scanner 100 is provided.
01 and a controller 2 that controls the scanner driver.
00 is connected.

The photosensitive recording medium 204 used here includes photosensitive microcapsules containing a cyan dye precursor, photosensitive microcapsules containing a magenta dye precursor, and photosensitive microcapsules containing a yellow dye precursor. It is assumed that the coating is uniformly distributed and applied to the surface of the base sheet. In addition, the photosensitive wavelength is 650 nm for the cyan capsule,
Magenta capsule is 550nm, yellow capsule is 45nm
It is set to 0 nm.

2 to 7 show the internal structure of the optical scanner 100. FIG. As shown in FIG. 2, this optical scanner 100 is
It is surrounded by a bottom plate 101, a glass plate 105, and a frame plate 107, and is formed in a sealed shape with an internal vacuum. A thermal head 1 serving as a heat generating means is provided on the inner bottom surface of the optical scanner 100.
10 are arranged. As its structure and main parts are shown in an enlarged manner in FIG. It is formed by

The hot cathode layer 102 is made of a non-quality or crystalline material such as barium oxide (BaO) or strontium oxide (SrO). On the other hand, a fluorescent element surface 104 is formed by coating the inner surface of the glass plate 105 with particulate fluorescent material.

Three types of fluorescent materials are used, the emission wavelengths of which match the sensitivity wavelengths of the cyan capsule, magenta capsule, and yellow capsule of the photosensitive recording medium 204. That is, a fluorescent material that emits red light (coloring wavelength 650 nm) corresponds to the cyan capsule, a fluorescent material that emits green light (coloring wavelength 550 nm) corresponds to the magenta capsule, and a blue light (coloring wavelength 550 nm) corresponds to the yellow capsule. A fluorescent substance that emits color (coloring wavelength: 450 nm) is used. The arrangement of each fluorescent substance (fluorescent cell) on the fluorescent element surface is determined by the fourth
As shown in the figure, R phosphor cells, Ql phosphor cells, and B phosphor cells are arranged in dots in a delta arrangement, or in stripes as shown in Fig. 5. Possible examples include things that have been done.

In the present invention, a microchannel plate 103, which is the electron multiplier of the present invention, is further provided in the internal vacuum space of the optical scanner 100.

The microchannel plate 103 has the heating element 1
Channeltron 10 with a diameter of about 10mm opposite to 14
A secondary electron emitting material layer 107 is formed on the inner wall surface of the channel through which each channeltron 106 penetrates as shown in FIG. 7. be. A voltage power source 115 is connected between the inlet and outlet of each channel tron 106 for accelerating and multiplying secondary electrons generated within the channel. Note that the exit side of each channeltron 106 is the fluorescent element surface 104.
It is opposite to. Furthermore, in this invention, as shown in FIG. A voltage power supply 116 is connected between the microchannel plate 103 and the fluorescent element surface 104, respectively.

In the color image forming apparatus configured in this way,
The thermal head 11 uses red, green, and blue color image information obtained by color-separating the original image.
When the predetermined heating element 114 generates heat, the hot cathode layer 102 in the vicinity thereof is heated. Then, thermoelectrons are emitted from the heated portion of the hot cathode layer 102 at a heating temperature of approximately IOOOK. The emitted thermoelectrons are incident on the corresponding channeltrons 106 of the microchannel plate 103 and collide with the secondary electron emitting material layer 107 on the inner wall of the channel. When the thermoelectrons collide with the secondary electron emitting material layer 107, secondary electrons are emitted, but the secondary electrons further repeatedly collide with the secondary electron emitting material layer 107, doubling the number of electrons. go. As a result, the channeltron 106 emits secondary electrons with a final gain of 100,000 times. These emitted secondary electrons are transferred to the fluorescent substance surface 10.
Collision in the designated area of 4. The fluorescent material surface 104 that the secondary electrons collide with emits light, but the wavelength of the emitted light at this time is matched to the sensitive wavelength range of the photosensitive recording medium 204, so the light emitted from the fluorescent material surface 104 is By irradiating a predetermined position on the surface of the photosensitive recording medium 204 through the optical lens system 203, the irradiated position on the surface of the recording medium is exposed, and color image information is recorded.

Note that the design of the thermal head 110, which is the heat generating means described above, can be modified in various ways. For example, in the example shown in FIG. 8, the heating element 114 may be made of a material that has both electrothermal properties and thermionic emission characteristics, such as tungsten (W) or thorium-tungsten (Th-W). In this case, it is known that a W heating element emits thermoelectrons at an energizing temperature of approximately 2700K, and a Th-w heating element emits thermoelectrons at an energizing temperature of approximately 1900K.

On the other hand, for the optical lens system 203, it is preferable to use an optical lens such as a rod lens array with a short focus in order to make the apparatus more compact, but it is also possible to perform exposure with the optical scanner and the photosensitive recording medium in complete contact with each other. It is possible. Of course, after exposure, visible color image information can be obtained by performing development according to each photosensitive recording medium.

[Effects of the Invention] As is clear from the detailed description above, the color image forming apparatus of the present invention converts thermoelectrons emitted based on each color image information obtained by color separation of a color original image into secondary At the same time as the energy is converted into electrons, the number of electrons is multiplied, and the secondary electrons are further accelerated to have high energy and collide with the surface of the fluorescent element, resulting in high output energy light emitted from the surface of the fluorescent element. Color image information is recorded by exposure on the surface of a photosensitive recording medium. Moreover, the selection of the fluorescent material on the surface of the fluorescent element matches the photosensitivity of the photosensitive recording medium. Therefore, printing with clear outlines is achieved on the surface of the photosensitive recording medium, and printing energy is efficiently applied to the exposure of the surface of the photosensitive recording medium, improving energy efficiency. Furthermore, since there is no need to use an expensive semiconductor laser or the like, there are many advantages such as lower device cost and more compact size.

[Brief explanation of drawings]

1 to 8 show embodiments embodying the present invention. FIG. 1 is a schematic configuration diagram of a color image forming apparatus in this embodiment, and FIG. 2 is the same as that shown in FIG. 1. 3 is an enlarged sectional view of the thermal head shown in FIG. 2, and FIGS. 4 and 5 are explanations of the correspondence between the arrangement of phosphor cells and the microchannel plate. Figure 6 is a plan view of the microchannel plate.
FIG. 7 is an enlarged sectional view thereof, and FIG. 8 is another embodiment of the thermal head. In the figure, 100 is an optical scanner, 103 is a microchannel plate, 104 is a fluorescent element surface, 110 is a thermal head, and 204 is a photosensitive recording medium. be.

Claims (1)

[Scope of Claims] 1. A color image forming apparatus that exposes a surface of a photosensitive recording medium having a plurality of photosensitive wavelength ranges to light based on color image information to produce a color image, the apparatus comprising: a heating means for emitting thermionic energy; an electron multiplier for emitting secondary electrons and multiplying the number of secondary electrons by the electron energy of the thermoelectrons emitted by the heating means; a secondary electron accelerating means for accelerating the secondary electrons; and a fluorescent means for emitting light having a wavelength matching each photosensitive wavelength range of the photosensitive recording medium upon incidence of the secondary electrons accelerated by the secondary electron accelerating means. 1. A color image forming apparatus comprising: a color image forming apparatus, wherein the wavelength light emitted by the fluorescent means is irradiated onto the surface of the photosensitive recording medium. 2. The photosensitive recording medium expresses a full-color image, and the fluorescent means has fluorescent cells that emit red light, green light, and blue light arranged regularly on the fluorescent surface. The color image forming apparatus according to claim 1, characterized in that: 3. Color image formation according to claim 2, wherein said fluorescent means has fluorescent cells that emit red light, green light, and blue light arranged in a delta array dot shape on a fluorescent surface. Device. 4. The color image forming apparatus according to claim 2, wherein the fluorescent means has fluorescent cells that emit red light, green light, and blue light arranged in stripes on the fluorescent surface. 5. In the photosensitive recording medium, photosensitive microcapsules containing a cyan dye precursor, photosensitive microcapsules containing a magenta dye precursor, and photosensitive microcapsules containing a yellow dye precursor are uniformly dispersed and coated on the base sheet surface. The color image forming apparatus according to claim 1, characterized in that: