JPS6111621A - Photodetecting device - Google Patents

Abstract

PURPOSE:To take measurement with high precision by positioning an annular light transmission part outside the visual field range of incident light and reducing its diameter successively from the tip of a cylindrical body to a photodetector. CONSTITUTION:The main device body 1 includes the photodetector 5 and is provided with an opening part 4 in the front surface of this photodetector, and a drain hole 7 is providing to the opening part 4. Further, plural light transmission parts 9a-9d of annular bodies 8 fitted on the internal surface of the opaque cylindrical body 6 which guides the incident light to the photodetector 5 are positioned outside the visual angle range of the incident light and decreased in diameter successively from the tip of the cylindrical body 6 to the photodetector 5. The incident light within the visual angle range A which is guided by the cylindrical body 6 reaches the photodetector 5 through the light transmission parts 9a-9d of the annular bodies 8 positioned outside the visual angle range. Thus, the annular bodies 8 function as light shield plate which cuts off undesirable light and the drain hole 7 is formed to prevent equivalent light screen brightness due to ambient light, thereby improving the measurement precision.

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention 1] The present invention relates to a light-receiving device that is mainly installed outdoors and can improve measurement accuracy.

[Technical background of the invention]

In general, environmental data acquisition devices that are installed outdoors, such as at airports, measure sky brightness and control various lighting and indicator lights based on this measurement data. A light receiver is installed to measure the brightness of external light incident on the brightness meter to obtain the necessary data. Since this luminance meter is installed outdoors, it is housed in a protective case with the light receiving section open, and the opening of the case is designed to prevent rainwater from entering the luminance meter or interference with measurements due to wild birds sneaking into the meter. A cylindrical body is attached. In other words, the eight cylindrical bodies were configured to guide the direction of incidence to the luminance meter and to remove infiltrating rainwater through a drainage hole drilled in the bottom.

[Problems with background technique circulation]

However, since the conventional cylindrical body does not have any infiltration prevention jig inside, rainwater may enter the case or wild birds may sneak in, which may adversely affect the measurement by the luminance meter. The effect was especially great on luminance meters that measure sky brightness by tilting them upward. Furthermore, even if a transparent plate such as glass is installed inside the cylindrical body to allow only light to pass through and prevent rainwater and wild birds from entering, measurement errors may occur due to water droplets and dust adhering to the glass surface, making it difficult to obtain accurate data. It had the disadvantage that it could no longer be obtained.

[Purpose of the invention]

The present invention has been made to eliminate the various drawbacks mentioned above, and an object of the present invention is to provide a light receiving device for rainwater when installed and used outdoors.

[Summary of the invention]

A device main body having a built-in light receiver and an opening on the front surface of the light receiver, and an opaque tube having a water drain hole attached to the opening and guiding light incident on the light receiver. and a plurality of ring bodies each having a light-transmitting part attached to a side surface of the cylindrical body, the light-transmitting part of the ring body being located outside the viewing angle range of the incident light, The gist is that the diameter of the shaped body is gradually decreased from the distal end direction toward the light receiver.

[Embodiments of the invention]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be explained below with reference to the drawings for one embodiment. (1), (1') are environmental data acquisition equipment (2)
), (1) is arranged in the secular direction, and (1') is the main body of the light receiving device arranged in an upwardly inclined shape. (1'), (
A light receiver (5) such as a luminance meter, for example, is housed facing the opening (4) of the light source 1'.

(6) is a light receiving part (3) with one end supported by the i-opening part (4).
It is a non-transparent cylindrical body that guides incident light, and is formed, for example, in a cylindrical shape, and has a plurality of drainage holes (7) bored in its bottom. (dan) is a plurality of rings (8a) (8b
) (8c) (8d) A ring body consisting of transparent parts (9a) (9b) (9c) (9d) each having a different diameter
and is attached to the inner surface of the cylindrical body (6). That is, these annular bodies are located outside the viewing angle range (A) of the incident light to the light receiver (5), and are arranged so that their diameters decrease by a sub-order from the tip of the cylindrical body (6) toward the light receiver. Translucent part (9
a) By arranging (9b) (・9c) (9d),
The ring (8d) with the transparent part (9d) is a cylindrical body (6)
The device is attached to the main body (1) by a fixture (11) that passes through a flange (10) extending from the opening (4) along the periphery.

(12) is an opening/closing door, (13) is a horizontal plane measuring device, (1
4) is a vertical plane measuring instrument. Next, we will discuss the effect.

The above-mentioned cylindrical body (6) is inserted into the front opening (
The light receiving device attached to 4) is arranged above the environmental data acquisition device (2) as shown in the first figure. Therefore, the incident light within the viewing angle range (A) guided by the cylindrical body (6) is transmitted to the transparent portion (9a) of the ring body (8) located outside the viewing angle range (
9b) Receiver (5) through (9c) and (9d)
Therefore, the annular body has the function of a front plate to exclude unwanted light, and by providing a drainage hole (7), it is possible to prevent the equivalent light curtain brightness caused by surrounding light. Therefore, measurement accuracy can be improved. In addition, the ring (phantom) prevents rainwater from entering, and even if there is some water, it can be removed to the outside through the drainage hole (7).It can also prevent wild birds from infiltrating. .

Of course, the shape of the annular body (6) may also be set corresponding to the shape of the cylindrical body (6).

〔Effect of the invention〕

As described in detail above, the present invention provides a light-impermeable cylindrical body that has a water drain hole in the opening of the main body of the device with a built-in light receiver and guides incident light to the light receiver, and the inside of this cylindrical body. A light-receiving device in which a plurality of ring bodies each having a light-transmitting part are formed such that the light-transmitting part is located outside the viewing angle range of the incident light, and the diameter of the cylindrical body gradually decreases from the tip of the cylindrical body toward the light-receiving direction. Therefore, when this light-receiving device is installed outdoors, the ring body prevents rainwater and wild birds from entering, and it also prevents the equivalent light curtain brightness caused by surrounding light from entering through the drainage holes. It has the special advantage of being able to perform measurements with extremely high precision, since it also has the function of a front plate that blocks the incidence of unnecessary light.

The drawings show an embodiment of the present invention, in which FIG. 1 is a perspective view showing the application to an environmental data acquisition device, and FIG. 2 is an enlarged sectional view of a light receiving device.

(1)...Device body, (4)...Opening, (5
)... Light receiver, (6)... Opaque cylindrical body,
(7)... Drain hole, (fl... Ring body, (9a
) (9b) (9c) (9d) ...transparent part.

Claims (1)

[Scope of Claims] A device main body that includes a built-in light receiver and has an opening in the front of the light receiver, and a water drain hole attached to the opening, and which prevents incident light from entering the light receiver. A guiding light-impermeable cylindrical body, and a plurality of ring bodies each having a light-transmitting part attached to a side surface of the cylindrical body, wherein the light-transmitting part of the ring body absorbs the incident light. 1. A light-receiving device, characterized in that it is located outside the viewing angle range and is formed so that the diameter of the cylindrical body gradually decreases from the distal end direction toward the light receiver.