JPH04314368A - Photodetector - Google Patents

Abstract

PURPOSE:To prevent malfunction caused by light outside, sunlight, etc., by a simple constitution. CONSTITUTION:A monolithically formed infrared ray remote sensor 3 with a photosensitive part 1 and a signal treatment circuit part 2 formed on the same substrate is contained in a tubular package 4 and a lens 5 is further formed on an upper part of the package 4. In a photodetector A wherein the infrared ray remote sensor 3 is arranged vertically and an optical axis L of the lens 5 is extended horizontally, the photosensitive part 1 constituting the infrared ray remote sensor 3 is arranged on the lens optical axis L and the signal treatment circuit part 2 is arranged in a vertically part of the photosensitive part 1.

Description

[Detailed description of the invention]

0001

[Industrial Field of Application] The present invention has an infrared light receiving element in which a light receiving part and a signal processing circuit part are formed continuously in the vertical direction, and a lens is mounted on the infrared light receiving element, and a lens optical axis is formed on the infrared light receiving element. The present invention relates to a light receiving device formed by extending horizontally.

0002

2. Description of the Related Art Generally, in order to remotely control television receivers, VTRs, etc., a light receiving device having an infrared remote sensor as a light receiving means is attached to a remote commander. As an infrared remote sensor in this light receiving device, a photodetector using a PIN diode has conventionally been used. Then, a light receiving section consisting of a photodetector using this PIN diode, a signal processing circuit section consisting of a circuit for amplifying the output signal from the light receiving section, a circuit for controlling the frequency band, etc. are housed in a metal box, for example. I try to use electromagnetic shielding. However, the metal box intended for electromagnetic shielding is expensive and requires many man-hours to assemble, which are factors that impede high productivity and cost reduction of the light receiving device.

In order to overcome the above-mentioned disadvantages, an infrared remote sensor has been proposed in which a light receiving section consisting of a photodiode and a signal processing circuit section are formed on the same substrate to form a monolithic structure.

As shown in FIGS. 3 and 4, the monolithic infrared remote sensor 11 is housed in a package 12, and a lens 13 is provided on the top of the package 12 to constitute a light receiving device B. I have to. Further, in order to easily receive the infrared light a from the remote commander, the light receiving device B is made horizontal and is attached to a set mounted on a television receiver, VTR, or the like.

That is, the infrared remote sensor 11 is arranged vertically, and the light receiving device B is arranged so that the optical axis L of the lens 13 is horizontal. Conventionally, the arrangement of the light receiving section 14 and the signal processing circuit section 15 constituting the infrared remote sensor 11 is such that the light receiving section 14 is arranged on the lens optical axis L, and the signal is placed at the lower part of the light receiving section 14 in the vertical direction. A processing circuit section 15 is arranged. Then, the infrared light a emitted from the remote commander is focused by the lens 13 and made to enter the light receiving section 14 of the infrared remote sensor 11,
The signal processing circuit section 15 demodulates the electric signal generated by the light receiving section 14 according to the amount of the incident light.

According to this light-receiving device B, a metal box can be made unnecessary, and high productivity and cost reduction of the light-receiving device can be realized.

[0007]

[Problems to be Solved by the Invention] However, in the conventional light-receiving device B, for example, external light from a lighting fixture (incandescent lamp, fluorescent lamp, etc.) 16 installed on the ceiling of the room, sunlight (simply, There is a problem in that it is easily influenced by external light) and malfunctions are likely to occur.

That is, when the light receiving device B is normally used, external light b enters the light receiving device B obliquely from above. The incident light (external light) b is refracted by the lens 13,
It reaches a position on the infrared remote sensor 11 below the optical axis L of the lens 13. In the case of the conventional light receiving device B, the light receiving section 14 is arranged on the lens optical axis L, and the light receiving section 14
Since the signal processing circuit section 15 is arranged at the lower part in the vertical direction, external light b directly enters the signal processing circuit section 15. Therefore, when the external light b directly enters the signal processing circuit section 15, an unnecessary photocurrent due to the external light b is generated in the circuit section 15, and the signal processing circuit section 15 operates with a minute signal. There is a disadvantage that the circuit malfunctions due to this photocurrent.

The present invention has been made in view of the above problems, and its purpose is to provide a light receiving device that has a simple configuration and can prevent malfunctions caused by external light, sunlight, etc. There is a particular thing.

0010

[Means for Solving the Problems] The present invention has a light receiving element 3 in which a light receiving section 1 and a signal processing circuit section 2 are arranged successively in the vertical direction, and a lens 5 is disposed on the light receiving element 3. In the light receiving device A, in which the optical axis L of the lens 5 is formed and the optical axis L of the lens 5 extends in the horizontal direction, the light receiving part 1 of the light receiving element 3 is arranged on the extension of the lens optical axis L, and the light receiving part 1 of the light receiving part 1 is arranged in the vertical direction. A signal processing circuit section 2 is arranged on the upper part.

[0011]

[Operation] According to the configuration of the present invention described above, since the signal processing circuit section 2 is arranged above the light receiving section 1 in the vertical direction,
Direct incidence of the external light b that enters the light receiving device A from obliquely above into the signal processing circuit section 2 can be avoided. Therefore, the photocurrent generated in the signal processing circuit section 2 by the external light b becomes very small, and malfunctions caused by the photocurrent can be reduced.

0012

Embodiments Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 and 2. FIG. 1 shows a light receiving device A according to this embodiment.
FIG. 2 is a schematic configuration diagram of the light receiving device A viewed from the side.

In this light receiving device A, for example, an N type impurity diffusion region is formed on a P type silicon substrate, and a light receiving portion 1 is constituted by a photodiode formed by the PN junction, and furthermore, a light receiving portion is formed on the same substrate. The signal processing circuit section 2 includes a monolithic infrared remote sensor 3 formed with a signal processing circuit section 2 consisting of a circuit for amplifying the output signal from the output signal 1 and a circuit for controlling the frequency band. The infrared remote sensor 3 is housed in a cylindrical package 4, and a lens 5 is formed on the top of the package 4 to form a light receiving device A.

Further, as shown in the figure, this light receiving device A is arranged horizontally so that it can easily receive infrared light a from a remote commander (not shown), such as a television receiver, a VTR, etc. It is attached to a set (not shown) mounted on the That is, the infrared remote sensor 3
is arranged vertically, and the light receiving device A is arranged horizontally so that the optical axis L of the lens 5 is horizontal. and,
The infrared light a emitted from the remote commander is transmitted to the lens 5.
The light is collected by the infrared remote sensor 3 and made to enter the light receiving section 1 of the infrared remote sensor 3, and the signal processing circuit section 2 demodulates an electrical signal corresponding to the amount of the incident light generated by the light receiving section 1.

Therefore, in this example, the arrangement of the light receiving section 1 and the signal processing circuit section 2 constituting the infrared remote sensor 3 is such that the light receiving section 1 is arranged on the lens optical axis L and the light receiving section 1 is arranged on the lens optical axis L, as shown in the figure. A signal processing circuit section 2 is arranged above the light receiving section 1 in the vertical direction.

In this case, in normal use, the light-receiving device A is mounted horizontally on a television receiver, VTR, etc., and the infrared light a from the remote commander is received from a substantially horizontal direction. When making a television receiver, VTR, etc. perform a desired operation by using b) enters the light receiving device A obliquely from above.

This incident light (external light) b is refracted by the lens 5 and reaches a position on the infrared remote sensor 3 below the optical axis L of the lens 5. In this example, the lens optical axis Since the signal processing circuit section 2 is arranged vertically above the light receiving section 1 arranged on the L, direct incidence of the external light b into the signal processing circuit section 2 can be avoided.

Therefore, according to the light receiving device A of this example, the photocurrent generated in the signal processing circuit section 2 by the external light b becomes very small, and malfunctions caused by the photocurrent can be reduced.

The light receiving device A according to this example is shown in FIGS. 3 and 4.
In order to realize the conventional light receiving device B shown in , it is sufficient to attach it to the set with the mounting direction upside down. In this way, the signal processing circuit section is arranged above the light receiving section in the vertical direction, so the light receiving device A of this example
You can get the same effect as .

[0020]

[Effects of the Invention] According to the light receiving device according to the present invention, malfunctions caused by external light, sunlight, etc. can be prevented with a simple configuration.

[Brief explanation of drawings]

FIG. 1 is a schematic configuration diagram of a light receiving device according to an embodiment, viewed from the front.

FIG. 2 is a schematic configuration diagram of the light-receiving device according to the present embodiment, viewed from the side.

FIG. 3 is a schematic configuration diagram of a conventional light receiving device viewed from the front.

FIG. 4 is a schematic configuration diagram of a conventional light receiving device viewed from the side.

[Explanation of symbols]

A. Light receiving device 1 Light receiving section 2 Signal processing circuit section 3 Infrared remote sensor 4 Package 5 Lens L Optical axis a Infrared light b. Outside light

Claims (1)

[Claims] 1. A light-receiving element including a light-receiving section and a signal processing circuit section, each of which is successively arranged in a vertical direction;
In a light receiving device in which a lens is formed on the light receiving element, and the optical axis of the lens extends horizontally, the light receiving part of the light receiving element is arranged on an extension of the optical axis of the lens, and the light receiving part of the light receiving part is arranged vertically. A light-receiving device characterized in that the signal processing circuit section is arranged at the upper part in the direction.