JPH0455317Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an optical printing device such as an optical printing printer or a copying machine, and particularly includes a mechanism for exposing photosensitive recording paper to form a latent image. This invention relates to an optical printing device.

[Background of the idea]

Photosensitive recording paper has microcapsules whose hardness changes depending on the amount of light exposure and a color developer that develops color upon contact with the contents of the microcapsules, which are coated on respective supports or on the same support. It is a recording medium. To form an image on this photosensitive recording paper, first, a latent image is formed by the change in hardness of the microcapsules by exposure according to the content of the document to be recorded, and then a latent image is formed by changing the hardness of the microcapsules using a pressure roll. The microcapsules are destroyed by pressure or heating, and developed by reacting with a color developer to develop color depending on the exposure state.

[Prior Art] Generally, optical printing devices for photosensitive recording paper use a linear light source such as a fluorescent lamp to form a latent image by exposing the original to light with an amount of light corresponding to the original. In this case, with a linear light source, the light intensity near both ends is generally lower than the middle, resulting in uneven light intensity, which inevitably causes the exposure amount to the photosensitive recording paper to become non-linear, causing the hardness of the microcapsules at both ends of the paper to increase. cannot be sufficiently increased. Therefore, there was a risk that the contents of the microcapsules would adhere to the paper feed rollers and pressure rollers that contact both ends of the paper, resulting in staining of the rollers themselves and staining of subsequent sheets.

[Purpose of invention]

In an optical printing device that forms a latent image by exposing photosensitive recording paper to light, the present invention effectively uses the amount of light emitted by an optical sensor for detecting the paper to sufficiently harden the microcapsules at both ends of the paper. An object of the present invention is to provide an optical printing device in which there is no possibility that the contents of microcapsules may adhere to a paper feed roller or a pressure roller that contacts both ends of a paper sheet, thereby causing stains on the roller itself or on subsequent sheets of paper.

[Structure of the idea]

This purpose is to use an optical printing device having the structure described in the claims of the utility model registration, that is, a light-emitting element that generates light including the wavelength to which the photosensitive recording paper is sensitive, and to attach the light to both ends of the photosensitive recording paper. This is accomplished by an optical printing device that is equipped with a device that exposes the paper to light and detects the presence or absence of paper.

[Effect of idea]

According to the optical printing device according to the present invention, in order to ensure that both edges of the paper are exposed while effectively using the light source for paper detection, It is possible to prevent transfer of unexposed capsules and to prevent staining of paper that passes through these rollers afterwards.

[Explanation of Examples]

FIG. 1 is an explanatory diagram showing the essential parts of the basic configuration of an optical printing apparatus according to the present invention. In the figure, a document 1 is placed on a document table 2, and receives a light beam concentrated on one side by a light source 3 and a reflective cover 4 via a light amount correction device 5. The reflected light from the original passes through an optical lens or lens array 6 and reaches a photosensitive recording paper, for example, a photosensitive pressure sensitive recording paper 7, forming a latent image on the recording paper. The photosensitive recording paper 7 is fed in the direction of an arrow 9 by a feed roller 8 .

Further, the paper sensor 10 detects the leading edge, trailing edge, presence or absence, distortion, etc. of the photosensitive recording paper 7. Generally, a light source with a wavelength to which the photosensitive recording paper is not sensitive is used for detection with an optical sensor, or a mechanical switch or the like is used. Therefore, the exposure amount adjustment for the photosensitive recording paper is performed exclusively by the light amount correction member 5 disposed between the light source and the document.

FIG. 2 is a characteristic curve of a fluorescent lamp, which is widely used as a light source in optical printing apparatuses and the like, whose horizontal axis represents the position in the tube length direction and whose vertical axis represents the amount of emitted light. In such a characteristic curve, the effective luminous amount is often used up to the part where the amount of light is reduced by 20% compared to the center of the tube.

The present invention focuses on the fact that the photosensitivity characteristics of microcapsules used in photosensitive and pressure-sensitive recording paper change not only depending on the intensity of the irradiated light beam, but also depending on the amount of exposure and therefore the applied energy, as shown in Figure 3. It is something.

FIG. 4, FIG. 5, and FIG. 6 are layout diagrams showing the structure of the optical printing apparatus according to the present invention. Components that are the same as those in FIG. 1 are given reference numerals with the same last digit. Here, a member corresponding to the light amount correcting device 5 in FIG. 1 is not provided. Instead, the paper sensor 20 includes a light emitting element 21 and a light receiving element 2 that generate wavelengths included in the sensitivity characteristics of the photosensitive recording paper 17.
It is configured as an optical sensor having 2. As is clear from FIGS. 5 and 6, the light emitting element 21 illuminates both ends of the photosensitive recording paper 17 in advance before exposure according to the content of the document is performed.
Since both ends of the paper are pinched and fed by the paper feed roller 18, it is desirable that the paper is sufficiently hardened. Therefore, it is convenient to adjust the luminous flux of the light emitting element 21 so that it is strong on both ends of the paper and suitable for shading correction on the inner side of the paper.
That is, illumination for the purpose of shedding correction accumulates light energy within the dead zone of the characteristic curve of FIG. As a result, during the subsequent exposure corresponding to the original image, a correction for insufficient light amount at both ends of the light source, that is, a shading correction is performed.

FIG. 7 shows an example of an apparatus configuration when using transfer type photosensitive pressure sensitive paper. The apparatus up to the feed roller 18 is the same as the above-mentioned apparatus, but then the latent image on the photosensitive recording paper 23 is transferred to the image transfer paper 24 by the pressure roller 25. Shaded areas 26 at both ends of the photosensitive and pressure sensitive paper 23 indicate that in the conventional configuration, incompletely cured microcapsules are likely to be destroyed due to the effect of reducing the luminous flux of the light source, and therefore the feed roller 18 and the pressure roller 25 are contaminated. tended to adhere. but,
In the optical printing apparatus according to the present invention, additional exposure is performed in advance by the light emitting element 21 in the paper sensor 20 as described above, and both this exposure and the original exposure for forming a latent image are used. Since sufficient exposure is thus performed, the microcapsules are sufficiently cured, and undesired destruction of the microcapsules by the feed roller 18 and the pressure roller 25 is prevented. Therefore, the frequency of cleaning and maintenance of the rollers can be reduced, and staining of the image transfer paper 24 via the rollers can be prevented.

According to each of the embodiments described above, the microcapsules at both ends of the paper can be sufficiently cured by actively utilizing the light flux generated by the light source of the paper sensor and performing additional exposure of the photosensitive paper. It is possible to prevent the feed roller, the pressure roller, etc. from getting soiled, thereby indirectly preventing the image transfer paper from getting soiled, and the labor and time required for cleaning and maintenance can be reduced. Furthermore, it is possible to additionally correct the exposure amount, that is, perform shading correction, and it is possible to obtain a good image.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram showing the basic configuration of an optical printing device. FIG. 2 is a longitudinal specific luminous flux curve of a linear light source. FIG. 3 is a photosensitivity curve of photosensitive recording paper. FIG. 4 is an explanatory diagram showing the basic configuration of the optical printing apparatus according to the present invention. FIG. 5 is a perspective view showing essential parts of the optical printing apparatus according to the present invention shown in FIG. 4. FIG. 6 is a view taken along the - arrow in FIG. FIG. 7 is a perspective view of the optical printing device according to the present invention configured as a transfer type. The correspondence of the main reference symbols in the figure is as follows. 11
...Original, 13...Light source, 14...Reflection cover,
16... Lens system, 17... Photosensitive recording paper, 18...
...Feed roller, 20...Paper detection sensor, 21...
...Light emitting element, 22 ... Light receiving element, 23 ... Photosensitive pressure sensitive paper, 24 ... Image transfer paper, 25 ... Pressure roller, 26 ... Microcapsule curing section.

Claims (1)

[Scope of Claim for Utility Model Registration] In an optical printing device that has a device that exposes photosensitive recording paper to form a latent image corresponding to the image of the original, a light emitting device that emits light that includes a wavelength to which the photosensitive recording paper is sensitive. What is claimed is: 1. An optical printing apparatus characterized by comprising a device that uses a device to additionally expose both ends of a photosensitive recording sheet and detects the presence or absence of the sheet.