JPH0531731B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to an infrared detection device that detects infrared rays from a plurality of detection areas.

[Background Art] Conventionally, this type of infrared detection device that detects infrared rays from a plurality of detection areas is as shown in FIG.
Concave mirrors 10 each corresponding to a plurality of detection areas...
In some cases, a condensing means 1 was formed to condense infrared rays from each detection area to one point, and an infrared detecting element 2 was provided at the condensing point of the condensing means 1. By the way, in this conventional example, the infrared detecting element 2 is attached to a mounting plate 11 that is rotatable in the direction of arrow A, the light emitting diode 3 is attached to the back surface of the mounting plate 11, and the mounting plate 11 is operated. By rotating the knob 11a by 180 degrees, the light emitting diode 3 is positioned at the light focusing point of the light collecting means 1, and the light emitting diode 3 is turned on, and the light from the light emitting diode 3 is transmitted through the light collecting means 1 to each detection point. It was designed to project light onto the area and confirm the detection area. However, with such conventional detecting hand area confirmation means, there is a problem that the rotation mechanism of the mounting plate 10 becomes complicated and the cost increases. Therefore, as shown in FIGS. 4 and 5, when using a condensing means 1 consisting of a plurality of (2×4) Fresnel lenses 12,
The infrared sensing element 2 and the light emitting diode 3 are arranged on the same side of the mounting plate 11, and the light from the light emitting diode 3 is projected through the lower Fresnel lens 12 (indicated by the dotted line in the figure). There was one in which the detection area corresponding to the upper Fresnel lens 12 could be checked without rotating the lens 11. However, in such conventional cases,
Lower Fresnel lens 1, which simplifies the configuration
There was an inconvenience that the detection area corresponding to 2 could not be confirmed. Therefore, as shown in FIGS. 6 and 7, a detection area confirmation lens 12a is added to each Fresnel lens 12, and the light from the light emitting diode 3 is passed through the detection area confirmation lens 12a to each detection area. However, there was a problem that the effective area of the infrared detection portion of the Fresnel lens 12 was reduced, resulting in poor detection sensitivity.
Since 2a cannot be made very large, the light beam emitted by the light emitting diode 3 becomes narrow, and the amount of light decreases, making it difficult to confirm the detection area when the detection area is far away.

[Object of the Invention] The present invention has been made in view of the above points, and its purpose is to provide an infrared detection device that has a simple configuration and can reliably confirm the detection area. be.

[Disclosure of the Invention] FIGS. 1 and 2 show an embodiment of the present invention. In an infrared detection device similar to the conventional example, a light-emitting surface having an area smaller than the light-receiving area of the infrared detection element 2 is provided. A light emitting diode 3 is attached, and when a detection area is confirmed, the light emitting diode 3 is turned on and the light from the light emitting diode 3 is projected onto each detection area via the condensing means 1. Specifically, the light emitting diode 3 is attached to the tip of an L-shaped support 4 that projects from the mounting plate 11. In other words,
The L-shaped support 4 protruding from the mounting plate 11 in this way
By attaching the light emitting diode 3 to the tip of the infrared sensing element 2, the light emitting diode 3 having an area smaller than the light receiving area is permanently installed on the light receiving surface of the infrared detecting element 2. Note that the reduction in detection sensitivity due to light shielding by the light emitting diode 3 is hardly a problem if the area of the light emitting diode 3 is made smaller than the light receiving area of the infrared detection element 2.

Now, infrared detection element 2 and light emitting diode 3
can be regarded as optically approximately the same position with respect to the condensing means 1, so when the light emitting diode 3 is turned on, the light from the light emitting diode 3 passes through each Fresnel lens 12 of the condensing means 1 to each detection area. The light is projected onto the
This projected light allows the detection area to be easily confirmed. in this case,
Since the light condensing means 1 for detection is also used as the light emitting means for confirmation, the configuration is simplified, and the light emitting means for confirmation can use a device with a large area equivalent to the light condensing means. It is now possible to reliably confirm each detection area.

By the way, in the embodiment, the light emitting diode 3 is blinked by a manual switch mechanism.
The light may be automatically turned on and off by a switch that is turned on and off when a cover (not shown) is fitted after the infrared detection device is installed.
That is, when the detection area is being set with the cover removed, the light emitting diode 3 is turned on, and when the detection area is set and the cover is attached, the light emitting diode 3 is turned off. The infrared detection operation may be started.

[Effects of the Invention] As described above, the present invention provides an infrared detection device comprising a condensing means for condensing infrared rays from a plurality of detection areas to one point, and an infrared detection element provided at the condensing point of the condensing means. In the device, a light-emitting diode with an area smaller than the light-receiving area is permanently installed on the light-receiving surface of the infrared detection element, and when the detection area is confirmed, the light-emitting diode is turned on and the light from the light-emitting diode is transmitted through the condensing means to each area. It is designed to project light onto the detection area, and the light condensing means for infrared detection is also used as the light emitting means for confirming the detection area, which simplifies the configuration, reduces costs, and makes it easier to use for confirmation. Since the light emitting means can have the same large area as the condensing means, it is possible to reliably check each detection area of the light emitted. Since the light-emitting diode is permanently mounted, there is no need for a moving mechanism to move the light-emitting diode, which simplifies the structure and reduces the cost. This makes it possible to place the light emitting diode close to the front of the light-receiving surface, and as a result, the entire light condensing means can be used as a confirmation light emitting means, increasing the amount of light and ensuring confirmation of the detection area. Moreover, even if the light-emitting diode is permanently installed in this way, the reduction in infrared sensitivity will not be a practical problem because the light-receiving area of the light-emitting diode is smaller than the light-receiving area of the light-receiving surface. effective.

[Brief explanation of the drawing]

Fig. 1 is a perspective view showing a schematic configuration of an embodiment of the present invention, Fig. 2 is a side view of the same as above, Fig. 3 is a perspective view of a conventional example, Fig. 4 is a perspective view of another conventional example, and Fig. 5 The figure is a side view showing the same operation as above, FIG. 6 is a perspective view of still another conventional example, and FIG. 7 is a side view showing the same operation. 1 is a condensing means, 2 is an infrared detecting element, and 3 is a light emitting diode.

Claims (1)

[Claims] 1. In an infrared detection device equipped with a condensing means that condenses infrared rays from a plurality of detection areas to one point, and an infrared detection element provided at the convergence point of the condensation means, a light-receiving area is provided on the light-receiving surface of the infrared detection element. A light emitting diode with a smaller area than the above is permanently installed, and when a detection area is confirmed, the light emitting diode is turned on and the light from the light emitting diode is projected onto each detection area via a condensing means. Infrared detection device.