JPS6343131A - Copying device - Google Patents

Abstract

PURPOSE:To suppress the generation of uneven light due to an array-like lens at the time of printing a projected image by receding the array-like lens from an optical path and forming the projected image directly on a line sensor. CONSTITUTION:Projected light beams from a projecting device 1 are folded by a reflection mirror 2 and its image is formed on the upper surface of an original plate glass 4. The projected image is formed on the line sensor 7 through the array-like lens 6 and read image information is transferred to a printer part 8. Only at the time of copying, the lens 6 is receded from the image forming optical path of the projecting system and the projecting system is directly focused on the sensor. Thereby, the positional relation between the lens 6 and the sensor 7 is set up so as not to interrupt the projected light flux.

Description

Detailed Description of the Invention B. Object of the Invention [Industrial Application Field] The present invention relates to a copying apparatus, and more particularly, to a copying apparatus, and more particularly, to a copying apparatus, and more particularly, to The present invention relates to a copying apparatus that forms an image on a line sensor 1-I using an array lens, and transfers image information read by the line sensor to a printer section for printing.

[Conventional technology]

FIG. 3 shows the configuration of a conventional copying apparatus that is capable of transmitting and enlarging a transparent original such as a slide film and copying its projected image in addition to normal original copying.
1 is the projection head of the transparent original. Projected light is reflected by mirror 2
The image is folded back and imaged on the upper surface of the document table glass 4.

3 is a Fresnel lens arranged to give directionality to a light beam that spreads in the projection direction; for example, a 5elfoc (registered trademark) lens array (hereinafter abbreviated as S, L, A) is used as an imaging lens. When used, it is necessary to convert the projection light into a parallel beam of light. FIG. 4 shows the state of the light flux in the system excluding the reflecting mirror.

The projected image projected onto the document table glass 4J- is focused on the line sensor 7 by the imaging lens 6, similar to a normal reflective document. The image information read by the line sensor 7 is
The image is transferred to the printer section 8 (for example, a laser printer) and printed.

In a copying apparatus having a configuration like Elm, the effective FNO on the magnification side of the projection lens is generally considered to be quite dark.

For example, use 35mm film for transparent originals.

Assuming that the document is enlarged to A4 size using a projection lens of F+to5.8, the projection magnification will be approximately 8 times, and the effective FNO on the enlargement side will be approximately 50.

By the way, when using S, L, and A as the imaging lens, 5
The imaging relationship of one elfoc lens is as shown in FIG. Generally, the degree of bulkiness m of S, L, and A is expressed as m.

FIG. 6 shows the relationship between the degree of overhang m and the unevenness of the amount of light (pitch unevenness) on the image plane. As shown in this figure, the greater the degree of overlap, the smoother the light on the imaging plane: I! The unevenness becomes smaller.

[Problem that Problem 191 attempts to solve] However, as mentioned earlier, the effective FNO on the magnification side of the projection lens becomes dark, and the spread angle k of the projection light beam in Fig. 7 becomes smaller than the viewing angle θ of the lens. When the diameter of the field of view 18 becomes smaller, the off-axis light beam is excluded from the lens, and the field of view 18 diameter xO becomes substantially smaller. This means that
As is clear from the equation (3), the degree of bulk m itself is reduced. In other words, there is a problem in that it leads to an increase in unevenness in the amount of light on the imaging plane.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide a copying apparatus that prevents the occurrence of unevenness in the amount of light due to the arrayed lenses.

[Means for solving the problem] The present invention provides an array of projection images of a transparent original projected onto a document table and reflection images from a document placed on the document table. In a copying apparatus that forms an image on a line sensor using a shaped lens, and transfers the image information read by the line sensor to a printer section for printing, when printing the projected image, the arrayed lens is removed from the optical path of the projected image. The copying apparatus is characterized in that it is configured to be retracted and the projected image is directly formed on the line senna.

[For production]

In the copying apparatus of the present invention, the array lens is retracted from the optical path of the projection image when printing the projection image, and the projection image is directly focused on the line sensor. Prevents uneven light from the lens.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a view of the image reading unit viewed from the short side of S, L, and A, and compares the conventional configuration “FIG. 1(a)” and the configuration of the present invention [1IA(b)J. This is what is shown.

First, in the conventional configuration shown in FIG. 1(a), the projection light beam from the exit pupil 9 of the projection lens is imaged on the upper surface of the document table glass 4, and is further imaged by the imaging lenses (S, L, A). The image is formed on the in-sensor 7], but with this configuration, the above-mentioned unevenness in the amount of light occurs.

Therefore, one aspect of the present invention, as shown in FIG. 1(b), retracts the imaging lenses (S, L, A) from the imaging optical path of the projection system only when copying the projection system.

At this time, it is necessary to adopt a configuration in which the focus position l of the projection system is such that the image is directly focused on the line sensor, not on the upper surface of the document table glass.

FIG. 2 shows the retracted state of S, L, and A. If the retracted S, L, and A6 are configured to scan together while keeping a certain distance from the line sensor 7,
With the line sensor 7 located at the end of the read image area A, it is necessary to arrange it at a position where the projection light beam is not blocked by the retreated S, L, and A6.

In short, one aspect of the present invention is to adopt a configuration in which the positional relationship between S, L, A6 and the line sensor 7 does not block the projected light beam, so that the line sensor 7 as described above has the following characteristics:
L, A6! ! Even if the line sensor 7 is retracted from S, L, and A6, the same effect can be obtained.

C. Effect of invention According to the present invention, as described hereinafter.

Since S, L, and A are removed from the imaging optical path of the projection lens and the projected image is enlarged and formed directly on the line sensor, it is possible to prevent pitch unevenness caused by S, L, and A. be.

[Brief explanation of the drawing]

FIG. 1 is a diagram of the image reading unit viewed from the short side of the array lens, FIG. 1(a) is a conventional configuration diagram, and FIG.
b) is a configuration diagram of the present invention, FIG. 2 is an explanatory diagram of the operation of the image reading unit in the copying apparatus of the present invention, FIG. 3 is a configuration diagram of the copying apparatus, and FIG.
FIG. 5 is a diagram showing the image formation relationship of the arrayed lens, FIG. 6 is a diagram explaining the relationship between the degree of overlapping and unevenness in light quantity, and FIG. 7 is a diagram showing the state of vignetting of off-axis light beams. 4... Original table, 6... Array lens, 7... Line sensor.

Claims (1)

[Claims] (1) The projected image of the transparent original projected onto the original platen and the reflected image from the original placed on the original platen are formed on a line sensor by an array lens, and are read by this line sensor. In a copying apparatus that transfers image information to a printer section for printing, when printing the projected image, the array lens is retracted from the optical path of the projected image, and the projected image is directly focused on the line sensor. A copying apparatus characterized in that it is configured as follows.