JPH09331075A - Infrared ray receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the receiving sensitivity of an infrared ray receiving part by a method in which infrared ray signals are reflected to be condensed while a condenser to enter the condensed infrared ray signals into a photo detecting element is provided. SOLUTION: An infrared ray receiver provided with a photodetector 2 for receiving infrared ray signals is provided with a condenser 10 to reflect and condense for entering the condensed infrared ray signals into the photodetector. For example, an infrared ray receiving part 100a is composed of a photodetecting filter 100b, a condensing plate 10 and photodiode 1. The inner wall side of the condensing plate 10 entirely funnel shaped is mirror surfaced to be reflectable of incoming infrared ray. In such a constitution, the infrared ray directly arrives at a condensing lens 5 through an optical path A while the infrared rays through the other optical paths B and C are reflected by the reflecting surface on the inner side of the condensing plate 10 to be entered into a semiconductor photodetector 2 transmitting the condensing lens 5.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an infrared receiving device having a light receiving element for receiving a transmitted infrared optical signal.

[0002]

2. Description of the Related Art FIG. 8 is a diagram showing a photodiode provided as a light receiving element in a light receiving portion of a conventional infrared receiver. The photodiode 1 is provided, for example, in the vicinity of a front panel of a device or the like equipped with a receiving device, receives an infrared light signal transmitted from the transmitting device side, and supplies it as an electric signal to a required receiving circuit unit in a subsequent stage. It is a thing. In a photodiode 1 shown in this figure, a semiconductor light receiving element 2 is provided for a lead frame 3. Further, an electrode 4 is drawn out from the lead frame 3. Then, the semiconductor light receiving element 2 and the lead frame 3
The main body of the photodiode 1 shown in this figure is constructed by molding the light source with the condenser lens 5. A transparent resin is used for the condenser lens 5. Further, since the photodiode 1 handles a weak signal, the shield S for preventing the influence of an external electrical disturbance covers the portion where the semiconductor light receiving element 2 is provided from the outer circumference of the condenser lens 5. Is provided in this way.

In the photodiode 1 having such a structure, the transmitted infrared light signal reaches the semiconductor light receiving element 2 via the condenser lens 5 and is received. The infrared light received in this manner is converted into, for example, a photocurrent corresponding to the amount of received light, and is output from the lead frame 3 via the electrode 4 to a receiving circuit section in the subsequent stage (not shown).

[0004]

By the way, when the transmitting direction of the infrared transmission signal is changed due to the change of the position on the transmitting device side, the light amount of the infrared optical signal that can be received by the photodiode on the receiving device side also fluctuates. It is naturally conceivable that an unstable received signal may be obtained in some cases. For this reason, it is preferable that the photodiode has a correspondingly high reception sensitivity for receiving infrared light.

For example, it is known that the receiving sensitivity of the photodiode 1 as shown in FIG. 8 generally depends on the area of the semiconductor light receiving element 2. That is, the receiving sensitivity becomes better as the area of the semiconductor light receiving element 2 becomes wider. However, when the area of the semiconductor light receiving element 2 is increased, the capacitive reactance component increases as the electrical characteristics of the semiconductor light receiving element 2 itself, which limits the operating speed of the semiconductor light receiving element 2. I know it will be done. Therefore, it is not appropriate to simply increase the area of the semiconductor light receiving element 2 in order to improve the receiving sensitivity. In practice, the operation speed of the semiconductor light receiving element 2 corresponding to the intended use of the receiving device should be ensured. Then, the area of the semiconductor light receiving element 2 is set.

Therefore, in the prior art, as shown in FIG. 8, a condenser lens 5 made of a transparent resin or the like is provided and the infrared light incident on the condenser lens 5 is condensed, so that a semiconductor light receiving element having a limited area is formed. The infrared light signal of as much light amount as possible arrives with respect to 2.

However, as described above, the condenser lens 5 is
Since the semiconductor light receiving element 2 and the lead frame 3 are formed so as to be enclosed in a relatively small size, the condenser lens has a lens diameter considerably larger than the size of the semiconductor light receiving element 2 and the lead frame 3. Forming 5 is not rational. That is, in order to obtain a larger amount of received light, there is a problem that the method of increasing the size of the condenser lens 5 as necessary is not practical.

[0008]

In order to solve the above-mentioned problems, the present invention is directed to an infrared receiving device having a light receiving element for receiving an infrared light signal, which reflects and collects the infrared light signal. Then, it is decided to provide a light condensing means for making the infrared light signal, which has been condensed, incident on the light receiving element. According to this configuration, the amount of received light that can be received by the light receiving element is increased by the light condensing means physically provided around the light receiving element.

[0009]

FIG. 7 shows an example of the configuration of an AV system that can be constructed using the infrared receiver of the embodiment of the present invention. In this case, the monitor stand 100 is prepared for installing the monitor device 102. An infrared light receiving portion 100a is provided on the front panel of the main body of the monitor stand 100.
In the infrared light receiving unit 100a, for example, a video / audio signal transmitted by an infrared light signal is received, converted into an electric signal, and supplied to a reception / demodulation circuit unit (not shown) provided inside the monitor stand 100. The infrared receiving device according to the present embodiment is related to a portion provided with a light emitting element (photodiode) in the infrared receiving unit 100a. In the infrared receiver, the received video signal and audio signal are subjected to required demodulation processing such as removal of subcarrier components, and finally the analog video signal V _OUT and audio signal A _OUT are output to the outside of the monitor stand 100 main body. Output. These video signal V _OUT and audio signal A
_OUT is connected, for example, so as to input to the monitor device 102 installed in the monitor stand 100.

The monitor stand 100 is, for example, provided with the transmission adapter 101 as a set to the user. The transmission adapter 101 can modulate a predetermined sub-carrier frequency by the input video signal and audio signal and emit and output it as an infrared light signal. The transmitted infrared light signal is transmitted by the infrared light receiving portion 100a of the monitor stand 100. The monitor device 1 receives the light and outputs the video signal V _OUT and the audio signal A _OUT as described above.
02. Instead of the monitor stand, an AV rack or the like having a shelf-like structure in which various AV devices can be installed may be used.

Such an AV system can be used as follows, for example. The user can connect, for example, some AV device 103 for outputting video / audio to the transmission adapter 101 with a cable or the like. Here, it is assumed that a game machine is connected as the AV device 103. By supplying the video / audio signal of the game machine to the transmission adapter 101,
It is transmitted as an infrared light signal from the transmission adapter 101. This transmission signal is received by the infrared receiving section 100a of the monitor stand 100 and converted into an electric signal,
The video signal V is demodulated by the internal infrared receiver.
_OUT and audio signal A _OUT are input to the monitor device 102. As a result, the monitor device 102 displays / outputs the image / sound of the game machine. That is, in a normal usage mode, the game machine is directly connected to the monitor device 102 by using a cable or the like, but the system shown in this figure does not need to do so, and the monitor stand 1
It is only necessary to wire-connect the monitor device 102 at the back of 00. Thereby, for example, in the room, the monitor device 10
Since a cable is not inserted between the game machine 2 and the game machine, it is possible to comfortably use the game machine and the like in the surrounding environment.

Next, the configuration of the infrared receiver according to the first embodiment of the present invention will be described. FIG. 1 schematically shows the internal structure of the infrared light receiving portion 100a shown in FIG. In the infrared light receiving section 100a shown in this figure, first, a light receiving filter 100b is provided so as to be exposed on the front panel of the monitor stand 100. The light receiving filter 100b is formed of, for example, a transparent resin that has been subjected to a coloring treatment so as to have a transmission characteristic that matches the wavelength of infrared light. Then, this light receiving filter 100
As shown in the figure, a photodiode 1 is provided on the inner wall side of b as a light receiving element. The photodiode 1 is provided with a semiconductor light receiving element 2 that converts received infrared light into an electric signal. The semiconductor light receiving element 2 is attached to the lead frame 3, and the photocurrent obtained by receiving light by the semiconductor light receiving element 2 is supplied to the electrode 4 via the lead frame 3. The electrode 4 is connected to, for example, a circuit board (not shown here) provided with a receiving / demodulating circuit system, and the optical signal received by the semiconductor light receiving element 2 is an electric signal in the receiving / demodulating circuit system in the subsequent stage. Will be supplied to. In the case of this embodiment, the infrared light signal of the video / audio transmitted from the transmission adapter 101 is received by the semiconductor light receiving element 2,
By supplying this light reception signal to the reception / demodulation circuit, it is finally output as the video signal V _OUT and the audio signal A _OUT .

The photodiode 1 of the present embodiment
For this, an existing photodiode may be used. That is, the structure may be the same as that of the photodiode 1 itself shown in FIG. Further, in the photodiode 1 shown in FIG. 1, the shield S for shielding the electric disturbance to the photodiode 1 as shown in FIG. 8 is not shown, but it is different from the photodiode 1 of the present embodiment. Alternatively, the shield S may be provided.

Then, the infrared light receiving portion 10 of the present embodiment
0a, as shown in FIG.
On the other hand, a light collector 10 is provided. An example of a specific shape of the light collector 10 is a perspective view of FIG. 2A and FIG. 2B.
In front view. Light collector 10 shown in FIGS.
Is formed to have a funnel-shaped overall shape after the opening 10a has a substantially elliptical shape that is long in the horizontal direction. And the photodiode 1 is
As can be seen from FIGS. 2A and 2B, the condenser lens 5 is attached so as to be exposed inside the condenser plate 10 at the center position of the bottom of the condenser plate 10. The inner wall side of the light collector 10 is made to be a mirror surface so as to be able to reflect the infrared light incident through the light receiving filter 100b. Further, the specific curved surface shape of the entire light collector 10 may be formed for the purpose of allowing reflected light to efficiently enter the photodiode 1.

In the infrared ray receiving portion 100a provided with the light collecting plate 10 as described above, the infrared ray is incident through the light receiving filter 100b in the state shown by the optical paths A, B and C as shown in FIG. 1, for example. Suppose The infrared light from the optical path A is the light that directly reaches the condenser lens 5, and after passing through the light receiving filter 100b as shown in the figure, is directly incident on the condenser lens 5 and is received by the semiconductor light receiving element 2. Further, the infrared light from the optical path B and the optical path C is reflected by the reflecting surface on the inner wall side of the light collector 10 to pass through the light collecting lens 5 and enter the semiconductor light receiving element 2.

For example, if the light collecting plate 10 is not provided for the photodiode 1 as shown in FIG. 8, the infrared light that can be received by the semiconductor light receiving element 2 is directly received by the light collecting lens 5. Only infrared light from the optical path A that arrives becomes. That is, the infrared light from the optical path B and the optical path C is light that does not originally reach the photodiode 1 unless the light collector 10 is provided. On the other hand, in the present embodiment, by providing the light collector 10,
Infrared light indicated by the optical paths A, B, C is applied to the semiconductor light receiving element 2
It becomes possible to receive light at, and the amount of light received by the semiconductor light receiving element 2 increases accordingly. That is, the receiving sensitivity of the photodiode 1 is improved.

The light collecting plate 10 of this embodiment is shown in FIG.
As described in (a) and (b), the opening 10a having a shape that is wide in the horizontal direction is provided to receive infrared light. That is, regarding the infrared light transmitted to the photodiode 1 from almost the horizontal direction,
The angle at which light can be received is made as wide as possible. For example, when considering a realistic installation environment of the transmission adapter 101 that transmits infrared light, it is assumed that the height of the installation position is almost the same as that of the infrared light receiving unit 100a in many cases. On the other hand, giving the degree of freedom to the installation position of the transmission adapter 101 in the horizontal direction also allows the user to view and listen to the monitor device 102 at a desired position, which improves the usability for the user. . Contrary to the above case as a practical use condition, when the angle at which the infrared light transmitted from the vertical direction can be received is wide, the degree of freedom of the installation position of the transmission adapter 101 becomes high. It is also conceivable to rotate the light collector plate 10 in the state shown in FIG. 2 by, for example, 90 degrees so that the opening 10a becomes wider in the vertical direction.

Further, in the case of the light collector 10 as shown in FIG. 2, the incident angle is limited in the direction in which the opening 10a becomes narrow, but this is positive in this embodiment. It is possible to limit the incidence of light from an originally unnecessary light source by applying to. As a specific example, for example, when light from a light source L such as ceiling illumination exists above the photodiode 1 as shown in FIG. 3, such light from the light source L is unnecessary for the photodiode 1. This is ambient light, and such incidence of ambient light reduces the reception sensitivity of the photodiode 1 accordingly. Therefore, for example, the vertical aperture and the overall shape of the light collecting plate 10 are set so as to be narrow enough to limit the incidence of the light of the light source L on the light collecting lens 5, and it is originally necessary. It is possible to allow only certain infrared light to enter the condenser lens 5. That is, it is possible to obtain an infrared receiver that is strong against ambient light.

FIG. 4 schematically shows a structure of a portion of a photodiode provided with a light collector as a receiver according to the second embodiment of the present invention. The photodiode 1 and the light collector 10A shown in this figure are also provided in the infrared ray receiving portion 100a as shown in FIG. 1 as the first embodiment, and the photodiode 1 is shown in FIG.
It may be the same as that used in the embodiment. Note that, in FIG. 4, the monitor stand 100 and the light receiving filter 100b illustrated in FIG. 1 are omitted. Further, the same parts as those in FIG.

The light collector 10A shown in this figure has an opening 1
Movable parts 11 and 11 which can change the diameter of 0a are provided. As a result, the light collector 10A can be operated to open and close around the movable parts 11, 11 as shown by the arrow in the figure, and the aperture of the opening 10a of the light collector 10A changes accordingly. It will be. For example, when the light collecting plate 10A is fully opened, it is preferable that the light collecting effect by the light collecting plate 10 is hardly obtained.
It should be noted that various concrete structures of the movable parts 11 and the structure of the light collector 10 </ b> A itself that accompanies this can be considered, and therefore detailed description thereof will be omitted. Further, the movable mechanism of the movable parts 11, 11 may be continuous or stepwise.

The movable parts 11, 11 of the light collector 10A are
For example, it can be adjusted by the user. And
The user can variably set the aperture of the light collector 10A in consideration of the change of the installation position of the transmission adapter 101, the incidence of unnecessary infrared light from the illumination or other transmission devices, and the like. As a result, it is possible to set an appropriate reception sensitivity of the photodiode 1 according to the usage environment of the user.

FIG. 5 schematically shows a structure of a photodiode portion provided with a light collector as a receiving device according to the third embodiment of the present invention. The photodiode 1 and the light collector 10B shown in this figure are also provided in the infrared light receiving portion 100a as shown in FIG. 1 and 4
The same parts as those described above are denoted by the same reference numerals and description thereof is omitted. Further, in FIG. 5, the monitor stand 100 shown in FIG. 1 is omitted and a part of the light receiving filter 100b is shown.

FIG. 5 shows the positional relationship between the light collector 10B and the photodiode 1 as viewed from the side, for example. In this case, the light collector 10B and the photodiode 1
Is provided as a separate body. Then, the infrared light that has passed through the light receiving filter 100b from the outside is temporarily collected by the light collector 1
By being reflected by 0B, the optical path of the photodiode 1 located below the light collector 10B is changed so that its optical path is changed. The infrared light thus condensed is incident on the semiconductor light receiving element 2 via the condenser lens 5. Note that, for example, in a plan view of FIG. 5, the infrared light transmitted through the light receiving filter 100b may be naturally bent by the light collector 10B in the optical path of the infrared light.

For example, due to the limitation of the mounting space of the infrared light receiving portion 100a and the like, the photodiode 1 is provided so as to face the transmission direction of the infrared light signal as in the case of FIGS. 1 and 4, for example. If not possible, the configuration of the present embodiment shown in FIG. 5 is effective. In this case, almost no light is directly incident on the photodiode 1, but since the light collecting plate 10B can collect an optical path over a relatively wide range, a corresponding amount of received light can be obtained, so that the reception sensitivity is also improved. It is possible.

FIG. 6 shows the configuration of the fourth embodiment of the present invention, and is the same as FIG. 1, FIG. 4 and FIG. 5 showing the configuration of the first to third embodiments so far. Are denoted by the same reference numerals and description thereof will be omitted. Light collector 1 of the present embodiment
The shield portion 12 is integrally formed at 0C. The light collector 10C is provided so that the shield portion 12 is attached to the peripheral portion of the photodiode 1. The overall outer diameter shape of the light collector 10C may be the same as that shown in FIG. 2, for example. The shield part 12 has the same function as the shield S shown in FIG. That is, it is provided to electrically shield the periphery of the main body of the photodiode 1 in consideration of the electrical disturbance affecting the photodiode 1. Therefore, as the light collector 10C of the present embodiment, a conductive material, or a material coated or plated with a conductive coating material is used. For example, if the light collecting plate 10C is plated with chrome, both the formation of the mirror surface of the light collecting plate 10C and the conductivity of the shield portion 12 can be obtained by this plating layer.

In this figure, a state in which the photodiode 1 is attached to the circuit board 13 is shown. Then, from the end of the shield portion 12, the lead 1
2a is pulled out, and the lead 12a is soldered to the ground pattern of the circuit board 13.

By providing the light collecting plate 10C having such a structure, when the photodiode 1 needs to be shielded, a separate work of attaching the shield is omitted.
That is, by attaching the light collector 10C integrated with the shield part 12, a shielding effect can be obtained.

Although the receiving device according to each of the above-described embodiments has been described as being provided in the monitor stand 100, it can be applied to receiving devices provided in other infrared transmitting / receiving systems. Further, the present invention is not limited to the structures shown in the drawings as the above-mentioned respective embodiments, and various modifications can be made according to actual use conditions and the like.

[0029]

As described above, the present invention is provided with the light condensing plate capable of reflecting and condensing the infrared light signal to make it enter the light receiving element. Since it is possible to increase the amount of light received by the element, it is possible to improve the light receiving sensitivity of the light receiving element accordingly, and it is possible to obtain a stable receiving operation regardless of changes in the situation on the transmitting side. ing. Further, by forming the light collecting plate into a shape having a wide opening in a specific direction, for example, the angle at which light can be received in the specific direction is enlarged or the angle at which light can be received is intentionally limited. Since it is possible to block the ambient light and increase the reception sensitivity for a necessary infrared signal, the reliability of the receiving device is improved. Furthermore, when the aperture of the light collector is adjustable, the receiving sensitivity of the light receiving element can be arbitrarily set according to the usage environment of the user, and a receiving device with improved usability can be obtained. .

[Brief description of drawings]

FIG. 1 is a side view schematically showing a configuration of a receiving device as a first exemplary embodiment of the present invention.

2A and 2B are a perspective view and a front view showing the shape of a light collector of the present embodiment.

FIG. 3 is a side view showing a state in which incidence of unnecessary light sources is restricted in the receiving device of the first embodiment.

FIG. 4 is a side view schematically showing a configuration of a receiving device according to a second embodiment.

FIG. 5 is a side view schematically showing a configuration of a receiving device according to a third embodiment.

FIG. 6 is a side view schematically showing a configuration of a receiving device according to a fourth embodiment.

[FIG. 7] A configured with the receiving device of the present embodiment
It is a perspective view showing an example of a V system.

FIG. 8 is a conventional receiver (photodiode).
It is a side view which shows the structure of.

[Explanation of reference numerals] 1 monitor stand, 2 semiconductor light receiving element, 3 lead frame, 4 electrode, 5 condensing lens, 10, 10A,
10B, 10C light collector, 10a opening, 11 movable part, 12 shield part, 13 circuit board, 14 ground pattern, 100 monitor stand, 100a infrared receiving part, 100b receiving filter

Claims (6)

[Claims] 1. An infrared receiving device having a light receiving element for receiving an infrared light signal, for reflecting and condensing the infrared light signal, and causing the collected infrared light signal to enter the light receiving element. An infrared receiving device characterized in that it is provided with a light collecting means. 2. The infrared receiving apparatus according to claim 1, wherein the light condensing unit is configured to have a movable mechanism section for changing the light condensing efficiency. 3. The infrared receiving device according to claim 1, wherein the light collecting means is formed in a shape having a light collecting effect on an infrared signal transmitted in a specific direction. . 4. The infrared receiving device according to claim 1, wherein the light condensing means is formed in a shape having a light blocking effect on light reaching from a specific direction. 5. The light receiving element is arranged such that an incident optical path of the light receiving element and an optical path of an infrared light signal to be transmitted do not correspond to each other, and the condensing unit is configured to transmit the infrared light signal of the transmitted infrared light signal. The infrared receiving device according to claim 1, wherein the infrared receiving device is arranged so as to be incident on the light receiving element by reflecting and refracting the optical path. 6. The infrared receiver according to claim 1, wherein the light condensing means is integrally formed with a shield means provided on the light receiving element body to provide an electric shielding effect. apparatus.