JPS5937771A - Figure reader - Google Patents

Abstract

PURPOSE:To realize a small and thin sized figure reader which reads an original accurately, by constituting with the 1st and the 2nd mirrors each of two plane mirrors which have a different specific angle. CONSTITUTION:An original is placed on a contact glass plate 1. The original is lightened up by an illumination fluorescent lamp 2 and reflected light from the original is reflected by the 1st mirror 8 and the 2nd mirror. Further, the light is image-formed on the light receiving surface of an image pickup element 4 through a fixed coupling lens 3. The 1st mirror 8 consists of two plane mirrors having a 45 deg. angle and the 2nd mirror 7 consists of two plane mirrors having a 90 deg. angle. For a scan, a wire 11 is fed at a speed (v) by a motor 16 to send a carriage 19 for supporting the illumination lamp 2 and the 1st mirror 8 at the speed (v) as shown by an arrow. Further, a carriage 20 for supporting the 2nd mirror is sent at a speed 1/2v as shown by an arrow.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a figure reading device that projects figure information onto a photoelectric conversion means using an optical system, and in particular, scans a figure plane while keeping the optical path length constant to generate an image at a fixed reading point or plane. The present invention relates to a figure reading device that projects images.

This type of graphic reading device is used as an input means for facsimile machines, intelligent copiers, etc. that perform recording and reproduction based on graphic signals.

FIG. 1 shows a conventional intelligent copier graphic reading device. As shown in FIG. 1, an original image on a contact glass plate 1 is illuminated with an illumination lamp 2, the reflected light from the original is reflected by a first mirror 6 and a second mirror 5, and an image is taken by a fixed coupling lens 3. An image is formed on the light receiving surface of the element (CCD) 4.

The illumination lamp 2, first mirror 6, and second mirror 5 are driven in the direction of the arrow to scan the document surface, but in order to keep the optical path length from the document to the coupling lens 3 constant regardless of the scanning position, When the lighting lamp 2 and the first mirror 6 move a distance t, the second mirror 5 moves 1/
You need to proceed to step 2.

This type of graphic reading device has the following drawbacks.

While the second mirror 5 scans the document surface, the direction of the normal to the plane of the second mirror 5 must always be kept in a constant direction (in the case of Figure 1, the direction of the normal to the second mirror is the scanning direction). Must be. In conventional reading devices, if the direction of the normal line of this mirror surface changes, the reading position of the document changes, and the problem is that it is impossible to continue reading the document accurately.

“Also, since the optical axis of the reading device is not parallel to the document surface, the length of the reading device in the thickness direction becomes large, making it difficult to realize a compact (thin) wIf/cutting device. There were drawbacks.

It is an object of the present invention to provide a figure reading device that maintains an accurate reading position regardless of fluctuations in the normal direction of the second g-plane. Our goal is to provide the following.

In the graphic reading device, the first mirror 6 and the second mirror 5 must always reflect light in a certain direction. However, while the document surface is being scanned, the first mirror 6 and the mirror 295 may be tilted due to play in the feed mechanism or the like.

Therefore, in the present invention, the first mirror 6 and the second mirror are
It constitutes mirror 5. Theory 1 and Theory 2 from Two Mirrors @
By using the t-configuration, even if the two mirrors are tilted,
The direction of light reflection does not change.

FIG. 2 shows the main parts of an embodiment of the present invention, and FIG. 3 shows the scanning means of the optical element of the present invention. 1 is a contact glass plate on which the original is placed. The original is illuminated with an illumination light (fluorescent lamp) 2, the reflected light from the original is reflected by the first fi 8 and the second mirror, and a fixed coupling lens 3 is used to capture an image sensor (eCD).
The image is formed on the light receiving surface of 4. The first mirror consists of two sets of plane mirrors with an angle of 45 degrees, and the second mirror consists of two sets of plane mirrors with an angle of 90 degrees.

FIG. 3 shows the f-travel mechanism of the optical device described above. This scanning mechanism consists of a wire 1 whose one end is fixed with a clamper 10.
1 to 2nd f#! The movable pulley 12 attached to the
Wrap it around Goo IJ 17 connected to 6, and tighten the tension.
The wire 11 is stretched around a pulley 18 and further stretched around a fixed pulley 15. The wire 11 is stretched around a movable pulley 12 attached to the first mirror 8 and the lighting lamp 2, and then folded back and the end of the wire is connected to a cranometer (
Fixed at 21.

The wire 11 is sent by the motor 16, and the speed at which the wire is sent is set to V.
Then, the illumination lamp 2 and the first mirror are sent at a speed V in the direction of the arrow in the figure, and the second mirror is sent at 1/2v in the direction of the arrow in the figure. Note that 19 in FIG. 3 is a carriage that supports the illumination lamp 2 and the first mirror, and 20 is a carriage that supports the second mirror.

According to the present invention, the first @ and the second @ for changing the optical path are
By configuring the mirror to have a sharp plane, even if the mirror is tilted due to play in the scanning mechanism while scanning the document surface, the direction of light reflection will not change, making it possible to read the document accurately. . Furthermore, the optical axis of the reading device can be configured to be parallel to the document surface, and a compact and thin reading device can be realized.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a conventional figure reading device, FIG. 2 is a diagram showing an embodiment of the optical system of the present invention, and FIG. 3 is a diagram showing an embodiment of the scanning system of the present invention. DESCRIPTION OF SYMBOLS 1...Glass plate, 2...Illumination lamp, 3...Coupling lens, 4...Imaging element. Kuzu l Figure East Z Figure χ3 Figure

Claims (1)

[Claims] 1. A first optical element consisting of a light source and a first folding mirror and a second optical element consisting of a second folding mirror are connected by a wire, and the first and second optical elements are connected by a wire. 1. A pattern reading device that drives a mirror back and forth at a speed ratio of 2:1, characterized in that the folding mirror of the second optical element is composed of two plane mirrors held at a constant angle. 2. A figure reading device according to claim 1, characterized in that the folding mirror of the second optical element is composed of two plane mirrors held at an angle of 90°. 3. A figure reading device according to claim 1, characterized in that the folding mirror of the first optical element is composed of two plane mirrors held at an angle of 45'.