JPS59220713A - Optical device - Google Patents

Abstract

PURPOSE:To secure sufficient light and to prevent a light sources from coming into contact with each other even when the pitch between conveyor rollers is narrowed down by providing a light guide member which guides light from the light sources to a subject. CONSTITUTION:A conveyor mechanism 11 for paper P, etc., as a body to be detected is provided with a couple of rollers 12 and 13 at a specific interval l''. Light from a discharge bulb 14 as the light source illuminates the paper P through a plate type glass body 18 as the light guide member. The irradiated paper P is detected by a photodetecting element 17 through an image forming lens 16. The surface of the paper P is irradiated with the light from the light source 14 through the glass body 18, so the intensity of light is nearly uniform over the entire area. Therefore, the pitch l'' between the rollers 12 and 13 can be narrowed down, so the paper P is conveyed stably and securely. The light guide member may be made of either a plate type plastic body or the plate type lens body.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to an optical device provided in, for example, a self-Wb ridge and removal device.

[Technical background of the invention and its problems]

As this type of optical device, for example, the one shown in FIG. 1 is known. That is, 1 in the figure is a conveyance mechanism for conveying paper sheets P, and this conveyance mechanism 1 has a pair of rollers 2, 2 and 3°3 at a predetermined interval! ' is arranged. And these pair of rollers 2, 2 and 3, 3
A pair of fluorescent lamps 4, 4 as a light source are arranged in the upper part between them.

When the paper sheet P is transported by the transport mechanism 1 and reaches the lower part of the fluorescent lamps 4, 4, it is irradiated with light from the fluorescent lamps 4, 4. This light is directed towards the paper sheet P as shown by the arrow.
The light is reflected by the light receiving element via an imaging lens (not shown), and is read.

By the way, in order to secure a larger amount of light, it is necessary to bring the fluorescent lamps 4, 4 closer to the light-receiving field of view (paper sheet surface). That is, the light emitting characteristics of the fluorescent lamps 4, 4 are determined by the distance from the tube surface of the fluorescent lamp 4, as shown in FIG. 2(a)! When is O, that is, on the surface, as shown in Figure 2(b), the luminous intensity is almost uniform over the entire area, but the peripheral luminous intensity decreases at a certain distance, as shown in Figure 2(c). This is because it exhibits characteristics (light unevenness).

However, when attempting to bring the fluorescent lamps 4.4 closer to the light-receiving field of view, conventionally, unless the pitch between the rollers 2 and 3 of the upsetting mechanism 1 is set wide, there is a risk that the fluorescent lamps 4 and 4 will come into contact with each other. was there. For this reason, the pitch between the rollers 2 and 3 has been widened, but when the pitch is widened, the paper sheet P cannot be stably conveyed, causing uneven conveyance and reducing detection accuracy.

[Purpose of the invention]

The present invention was made with attention to the above-mentioned problem, and its purpose is to ensure a sufficient base area and to prevent the light sources from coming into contact with each other even if the pitch between the conveyor rollers is narrowed. The present invention aims to provide an optical device.

[Summary of the invention]

In order to achieve the above object, the present invention includes a light guide member that guides light from a light source to an object to be detected.

[Embodiments of the invention]

The present invention will be explained below with reference to an embodiment shown in FIG. In the figure, reference numeral 11 denotes a conveyance mechanism for conveying a paper sheet P as an object to be detected, and this conveyance mechanism 11 includes a pair of four-wheels 12, 12.
, 13.13 are arranged at a predetermined interval f'. Furthermore, a fluorescent lamp 14, 14, which is a discharge tube, is provided as a light source on the upper side of the transport mechanism 1. Also, 15
is a reflected optical path, and an imaging lens 16 and a light receiving element 17 are disposed in this reflected optical path 15. On the other hand, a plate-shaped glass body 18 as a light guiding member is provided between the fluorescent lamp 14.14 and the conveyance surface 19 of the paper sheet P, and the fluorescent lamp 14.14 The paper sheets P are irradiated with light from the paper sheets P. Fluorescent lamp 14.1 above
4 is a slit type, and the entire luminous flux is emitted from the slit. The width d of the plate glass body 18 is freely set according to the slit angle of the fluorescent lamp 14, 14, and the same applies to the length A''.

However, when the paper sheet P is transported by the transport mechanism 1 and faces the lower end surface of the plate glass body 18, one fluorescent lamp 14.
The light from 14 is irradiated onto the paper sheet P via the plate glass body 18.18. Then, this irradiated light is applied to the paper sheet P.
The light is reflected by the light receiving element 17 via the imaging lens 16, and is photoelectrically converted and read.

As mentioned above, since the light from the fluorescent lamp 14.14 is irradiated onto the paper sheets P through the plate glass body 18.18, even if the fluorescent lamp 14.14 is separated from the paper sheets P, the light emitted from the sheet J. is a luminescent laser that is almost uniform over the entire area, and there is no decrease in the amount of peripheral light. Therefore, the roller 12 of the roller 11,
It becomes possible to narrow the pitch by 12, and the paper sheets 8P can be transported stably and reliably.

Further, by providing 4i1i of plate glass bodies 18.18, the luminous flux of the fluorescent lamps 14.14 can be guided to the paper sheet P even if the light receiving element 17 is provided close to the exchange surface 19f.

Furthermore, by using the slit type fluorescent lamps 14 and 14, it is possible to guide the paper sheets P in a total luminous flux.

In the above embodiment, the light irradiated onto the paper sheet P is reflected and received; however, the light irradiated onto the paper sheet P is not limited to this, and as shown in FIG. The light may be transmitted and received.

Furthermore, the light guide member is not limited to a plate-shaped glass body;
A plate-shaped plastic body or a plate-shaped lens body may be used.

〔Effect of the invention〕

As explained above, since the present invention is equipped with a light guide member that guides the light from the light source to the detected object, the amount of light irradiated to the detected object is reduced (attenuated) even if the light source is moved away from the detected object.
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Therefore, the arrangement pitch of the finger speed rollers of the detected object can be narrowed as much as possible, and the detected object can be stably and reliably conveyed, and the detection accuracy can be improved.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a conventional optical device, FIG. 2 is a graph showing its fluorescent characteristics, FIG. 3 is a block diagram showing an optical device as an embodiment of the present invention, and FIG. 4 is a block diagram showing the present invention. Other embodiments of the invention are shown (U causes. 14, J4... light source (luminescent lamp), P... detected object (Ij (leaf #;+'t), 18.18...・Light guide member (plate glass).Patent attorney Takehiko Suzue Figure 1 Figure 2 Commissioner of the Patent Office ■ Kazuo Wakasugi 1. Indication of the case Patent application No. 1987-96167 2, Name of the invention Optical device 3, Relationship to the case of the person making the amendment Patent J.S.P.

Claims (2)

[Claims] (1) In a device in which a light source irradiates a detected object with light and a light receiving element receives light from the detected object,
An optical device comprising a light guide member that guides light from the light source to the detected object. (2) The optical device according to claim 1, wherein the light guide member is a plate-shaped lens body, a glass body, or a plastic body.