JPS6318863A - Image reader - Google Patents

Abstract

PURPOSE:To execute the magnifying copying of the original picture of a small area such as a slide with a good resolution by arranging a Fresnel lens on the platen glass of an image reader, projecting the image of the slide on it and executing the photoelectric converting with a projected image. CONSTITUTION:To a slide projector 10, for example, a color slide of 35 mm is set, and the image of the color slide is projected through a mirror 11 onto a Fresnel lens 12. When the units having a rod lens array 4 and a color photographing element 5 are scanned in the direction vertical to the length-wise direction of these, the information is obtained in which a 35 mm color slide is magnified to an A3 size. Consequently, the information is once stored into a memory, the information is guided directly to a color printer and the image magnified to the A3 size can be outputted. Consequently, as conventionally, it is unnecessary to overlap many pieces of the image information of the same contents and obtain the magnified image information, and the resolution can be increased.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an image reading device, and in particular to a 35
The present invention relates to an image reading device suitable for enlarging and reading a small area original image such as a mm color slide.

(Prior Art) Conventionally, a 351III1 color slide is read, for example, A3 size (420 mm x 297 mm).
When enlarging an image to a size of 200 yen and making a color copy, the apparatus shown in FIG. 4 was used.

This figure schematically shows the configuration of the main parts of a conventional image reading device. In the figure, 1 is a platen glass, on which a 35 mm color slide 2 to be read is placed. Below the platen glass 1, light sources 3a and 3b such as fluorescent lamps are installed parallel to the platen glass 1, and below the center of the lights r7.3a and 3b, the platen glass 1 and parallel to the light sources are installed. A rod lens array 4 of approximately equal width is provided.

Further, below the rod lens array 4, a color imaging cable 5 of approximately equal length is provided parallel to the rod lens array 4.

The light sources 3a, 3b, rod lens array 4, and color imaging cable 5 are integrally assembled by units 1 and 6 surrounded by a dashed line.

The color image sensor 5 has red (R), green (G) and ? ? (B
It has an FM structure in which image pickup elements equipped with three color filters ( ) are cyclically connected, and its upper surface has the shape of a parallelogram as shown in FIG. This color imaging probe 5 can normally read images at a sampling density of 8 dots/mm to 16 dots 101111.

Now, using an image reading device having such a configuration,
For example, read a 35mm color slide and print it on A3
When enlarging to a larger size (approximately 10 times enlargement), first place the 35 mm color slide 2 at a predetermined position on the platen glass 1, and stop the unit 6 at the starting position.
Next, the lights Lf3a and 3b are turned on, and the light reflected from the 35 mm color slide 2 is received by the rod lens array 4 and focused on the color imaging cord 5. Next, the light incident on the color image sensor 5 is converted into an electric signal corresponding to each color by the RSG, an 83-color image sensor, and this is stored in a memo (not shown) for one month.

Next, the above operations are performed continuously by moving the unit 6 in the direction indicated by the arrow. Then, when the 35 mm color slide 2 is finished reading, the reading of the image information ends.

Through the above operations, image information for one 3511Im color slide is stored in the memory at the same size.

Thereafter, based on the image information stored in the memory, an enlargement process is performed to increase the image by about 10 times.

(Problems to be Solved by the Invention) In this case, the memory stores image information of the same size read by the color imaging probe 5 at a sampling density of 8 dots/mm to 16 dots/mm. Therefore, when obtaining an enlarged copy of A3 size, approximately 10 pieces of the same pixel information (i.e. image information) are interpolated.
This is done by enlarging the image information to twice the size and printing it out using a color printer.

For this reason, there is a problem in that the resolution of the enlarged image obtained by enlarged copying is thick (deteriorated).

SUMMARY OF THE INVENTION An object of the present invention is to eliminate the problems of the prior art and to provide an image reading device that can enlarge a small black and white slide or a color slide with high resolution.

The present invention has been made to solve the above-mentioned problems.

(Means and operations for solving the problems) In order to solve the above problems, the present invention provides a method for combining a plurality of photosensitive pixels into one
An image reading device using imaging probes arranged in three dimensions, which includes a Fresnel lens installed on a platen surface and a means for projecting an enlarged optical image onto the platen surface, allows an original image of a small area to be read. It is unique in that it allows for high-resolution, enlarged copies.

(Example) The present invention will be described in detail below with reference to the drawings.

FIG. 1 is a perspective view of an embodiment of the present invention. Also, the second
The figure shows its side view.

In the figure, 10 is a slide projector, 11 is a mirror that reflects incident light, and 12 is a Fresnel lens that is detachably provided on the platen glass of the image reading device. 13 is the unit 6 shown in FIG.
This is a housing housing a unit from which the light sources 3a, 31) have been removed or turned off, and the illustration of the unit is omitted. The lens of the projector 10 is detachably attached to a substantially focal position of the Fresnel lens 12.

In this embodiment, a color slide of, for example, 35 mm is placed in the slide projector 10, and an image of the color slide is projected onto the Fresnel lens 12 via the mirror 11. At this time, the magnification is adjusted so that the size of the image projected onto the Fresnel lens 12 becomes A3 size.

As mentioned above, the lens of the slide projector 10 is placed at approximately the focal point of the Fresnel lens 12.
After the light forming the image of the slide on the Fresnel lens 12 passes through the Fresnel lens 12, it becomes parallel to a rod lens array (not shown). The light passing through the rod lens array is focused on the color image sensor 5 and converted into an electrical signal, similar to the conventional device.

Therefore, by scanning a unit having at least the rod lens array 4 and the color image sensor 5 in a direction perpendicular to their longitudinal direction, information obtained by enlarging the 35IIlff+color slide to A3 size can be obtained. Therefore, by temporarily storing this information in the memory, or directly leading it to the color printer without storing it in the memory, it is possible to output an image enlarged to A3 size.

According to this embodiment, after optically enlarging the slide to a desired magnification, it is digitally read using a same-magnification image reading device at a normal sampling density. It is no longer necessary to obtain enlarged image information by duplicating many pieces of image information with the same content, and resolution can be increased.

Next, a second embodiment of the present invention will be described. This example is
In the first embodiment, a spherical lens is used instead of the same-magnification rod lens array, and a high-density color image sensor with a short length is used as the same-magnification color image sensor. .

It is a simple explanatory diagram of the third drawing. 10 and 12 are the same slide projector and Fresnel lens as shown in FIG. 1, 14 is the spherical lens, and 15 is a high-density color image sensor.

Note that in this embodiment, the slide projector 10
The lens 10a is placed at a position away from the focal position of the Fresnel lens element 2.

According to this embodiment, an enlarged image of the original image is obtained by photoelectrically converting the optically enlarged image using a high-density color image sensor, so that a high-resolution enlarged image is obtained as in the first embodiment. be able to.

(Effects of the Invention) According to the present invention, a Fresnel lens is placed on the platen glass of the image reading device, an image of the slide is projected onto it, and the projected image is used for photoelectric conversion. It is possible to make an enlarged copy of a small-area original image, such as, with good resolution.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of another embodiment of the present invention, Fig. 2 is a side view thereof, Fig. 3 is an explanatory diagram of another embodiment of the invention, Fig. 4 is a perspective view of a conventional device, and Fig. 5 is a perspective view of another embodiment of the present invention. The figure shows a plan view of a color image sensor. DESCRIPTION OF SYMBOLS 1...Platen glass, 4...Rod lens array, 5...Color image sensor, 6...Unit, 10...
...Slide projector, 11...Mirror, 12.
... Fresnel lens, 13... Case agent Patent attorney Michito Hiraki and one other person Figure 1 Figure 2 Figure 3 Figure 4 Figure 5

Claims (2)

[Claims] (1) An image reading device using an image sensor having a plurality of photosensitive pixels arranged one-dimensionally includes a Fresnel lens installed on a platen surface and a means for projecting an enlarged optical image onto the platen surface. An image reading device comprising: (2) The image reading device according to claim 1, wherein the Fresnel lens is detachable.