JPS58174937A - Illuminating device of copying machine - Google Patents

Abstract

PURPOSE:To reduce the loss of light as far as possible and to enable the efficient irradiation of light to an original surface, by forming the part of a reflecting mirror where the reflected light of a slit exposure type is shielded by a light source into a diffuse reflection surface. CONSTITUTION:The light from a light source 1 is condensed to an original surface 4 by using an elliptical reflecting mirror 2 having a section consisting a part of the ellipse having a light source 1 such as a barlike halogen lamp at one focus and the light is condensed to the irradiation position of an original by a circular reflecting mirror 3 provided on the opposite side, whereby slit exposure is accomplished. If the reflection surface in the shaded part A of the mirror 2 is formed by satin finishing as a diffuse reflection surface, the light emitted from the light source 1 is diffused and reflected and is further reflected again in the part except the shaded part A of the mirror, from which the light is irradiated to the original surface 4 or through the mirror 3 to the surface 4.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides an illumination device i11 for a copying machine that applies slit and cross exposure to a document surface by relative movement, and exposes a photoreceptor to the image displayed on the document surface to form a moat. It is related to.

An illumination device in a slit four-light type copying machine needs to efficiently condense and irradiate the document surface with light emitted from a light source.

Conventionally, the first lighting device for a copying machine such as the one mentioned above is
The configuration shown in the figure is used.

In other words, an elliptical reflector 2 having a cross section of a part of an ellipse with light #1 at its focal point, such as a rod-shaped halogen rung, is used to condense the light from the light source 1 onto the document surface 4.
A circular reflector "iN3" having a cross section consisting of a part of a circle is provided on the opposite side of the elliptical reflector 20 to reflect the light from the elliptical reflector 2, condense it at the document irradiation position by the ellipse reflector 2, and sliver it onto the document surface 4. It was designed to do the same thing.

However, this type of conventional device has the disadvantage that the light reflected by the shaded area A of the elliptical reflector 2 is diverted by the light source 1, and the light is lost by that amount, which lowers the usage efficiency. was there. Therefore, the purpose of the present invention is to improve the drawbacks of the prior art as described above and to minimize the loss as much as possible.
The goal is to obtain a lighting device with the benefit of utilization efficiency.

The present invention is characterized in that, of the reflecting surface of the elliptical reflection 'a2 shown in FIG. 1, the portion A, which is filled with the reflected light by the light source 1, is made into a diffuse reflecting surface.

In the first embodiment of the present invention, the reflective surface of the shaded area A of the elliptical reflective mirror 2 in FIG. By diffusely reflecting the light, reflected light that is not blocked by the light source 1 is generated. These reflected lights reach a portion of the elliptical reflecting mirror 2 other than the shaded area A, are further reflected there, and from there reach the original surface 4 or via the circular reflecting mirror 3.

Another embodiment of the invention is shown in FIG. In this example, the elliptical reflection 1Iii in the example of FIG. 1! The only difference is that I2 is a flat reflecting mirror 5 formed by a combination of flat mirrors.
The rest of the structure and technology '8' are the same as those in FIG.

In addition, in the two embodiments shown in FIGS. 1 and 3, the shaded area A is made of satin material and used as a diffuse reflection surface, but there is also a method of painting it white, or, for example, as shown in FIGS. 4 and 5. There is a method of creating a diffuse reflection surface by adding unevenness to the reflection surface.

As explained above, according to the lighting device of the present invention, the utilization efficiency of the original light emitted from the light source 1 is higher than 9, and compared to the conventional one, in the embodiment shown in FIG. 1 can be reduced.

In addition, since it is painted white to form a diffuse reflection surface, it is generally somewhat less effective than those made of i-work or pear-skinned materials.

In addition, when the shape shown in Figures 4 and 5 is used as a diffuse reflection surface, the effect is greater than that of a frame material, but it is somewhat disadvantageous in terms of cost.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of the lighting device, FIG. 2 is an enlarged view of the vicinity of the light source in FIG. 1, FIG. 3 is a sectional view showing another embodiment of the lighting device of the present invention, and FIG. 4 and FIG. 5 are cross-sectional views showing other specific examples of the diffuse reflection surface. Symbols in the figure: l... Light source; 2... Elliptical reflecting mirror; 3... Circular reflecting mirror; 4... Original cover stand; 5... Flat reflecting mirror. (3 others)

Claims (1)

[Claims] In the illumination system r1tVC of a slit exposure type copying machine. An illumination device for a copying machine, characterized in that it has a diffuse reflection surface that is a portion of a reflective mirror surface where reflected light is blocked by a light source.