Electrically shielded photodiode

Abstract

The utility model discloses an electric shielding photodiode, which relates to the technical field of electric shielding and comprises a photojunction, a positive electrode pin, a negative electrode pin, a grounding pin and a metal shell. The photoelectric junction is a PN junction or a PIN junction; the photojunction is fixed in the metal shell; the photojunction is used for converting an optical signal into an electric signal under a conduction condition; one end of the positive electrode pin penetrates through the metal shell and is connected with one end of the photojunction; one end of the cathode pin passes through the metal shell and is connected with the other end of the photojunction; one end of the grounding pin is connected with the metal shell; and the metal shell is used for realizing electric shielding of the photojunction through the grounding pin. Electric shielding of the photodiode is achieved through the structure of the photodiode, and the installation process is convenient and fast.

Description

Technical Field

[0001] The utility model relates to the technical field of electric shielding, in particular to an electric shielding photodiode. Background Art

[0002] In the prior art, since some devices or circuits have high requirements for the current generated by the photodiode, it is generally necessary to take electrical shielding measures for the photodiode. The existing shielding method is usually to wrap a layer of metal aluminum foil on the outside of the photodiode, and then ground the metal aluminum foil to use the metal aluminum foil to electrically shield the photodiode. The whole process not only requires the provision of additional shielding materials, but is also time-consuming and labor-intensive. Utility Model Content

[0003] The purpose of the embodiment of the utility model is to provide an electrically shielded photodiode, which can realize the electrical shielding of the photodiode by utilizing its own structure, and the installation process is convenient and quick.

[0004] To achieve the above purpose, the present invention provides the following solutions:

[0005] An electrically shielded photodiode comprises: a photoelectric junction, a positive electrode pin, a negative electrode pin, a grounding pin and a metal shell; the photoelectric junction is a PN junction or a PIN junction;

[0006] The photoelectric junction is fixed inside the metal shell; the photoelectric junction is used to convert the optical signal into an electrical signal under the condition of conduction;

[0007] One end of the positive electrode pin passes through the metal shell and is connected to one end of the photoelectric junction; one end of the negative electrode pin passes through the metal shell and is connected to the other end of the photoelectric junction; one end of the grounding pin is connected to the metal shell;

[0008] The metal shell is used to achieve electrical shielding of the photoelectric junction through the ground pin.

[0009] Optionally, the metal shell specifically includes: a metal tube seat and a metal tube cap;

[0010] The metal tube cap is fixed on the metal tube seat; the metal tube cap and the metal tube seat form a cavity; the photoelectric junction is fixed in the cavity; one end of the positive pin passes through the metal tube seat and is connected to one end of the photoelectric junction; one end of the negative pin passes through the metal tube seat and is connected to the other end of the photoelectric junction; one end of the ground pin is connected to the metal tube seat.

[0011] According to the specific embodiments provided by the embodiments of the present invention, the present invention discloses the following technical effects:

[0012] In addition to the positive pin and the negative pin, the photodiode of the embodiment of the utility model is also provided with a ground pin, and the ground pin is connected to the metal shell of the photodiode. During the use of the photodiode, there is no need to perform other shielding treatments on the photodiode. The electrical shielding of the photodiode can be achieved by simply grounding the ground pin. The whole process is simple, convenient and fast. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0014] Figure 1 A front view of an electrically shielded photodiode provided by an embodiment of the utility model;

[0015] Figure 2 A top view of an electrically shielded photodiode provided in an embodiment of the utility model.

[0016] Explanation of symbols:

[0017] Positive pin-1, negative pin-2, ground pin-3, metal tube socket-4, indicator protrusion-41, metal tube cap-5. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] The utility model aims to provide an electrically shielded photodiode, which can realize the electrical shielding of the photodiode by utilizing its own structure, and the installation process is convenient and quick.

[0020] In order to make the above-mentioned purposes, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0021] Figure 1 An exemplary structure of an electrically shielded photodiode is shown, and various parts of the structure are described in detail below.

[0022] See also Figure 1, an electrically shielded photodiode, comprising: a photoelectric junction, a positive pin 1, a negative pin 2, a ground pin 3 and a metal shell; the photoelectric junction is a PN junction or a PIN junction.

[0023] Specifically, the photoelectric junction is fixed inside the metal shell; the photoelectric junction is used to convert the optical signal into an electrical signal under the condition of conduction; one end of the positive pin 1 passes through the metal shell and is connected to one end of the photoelectric junction; the other end of the positive pin 1 is used to connect the positive pole of the circuit; one end of the negative pin 2 passes through the metal shell and is connected to the other end of the photoelectric junction; the other end of the negative pin 2 is used to connect the negative pole of the circuit; one end of the grounding pin 3 is connected to the metal shell; the other end of the grounding pin 3 is used for grounding; the metal shell is used to achieve electrical shielding of the photoelectric junction through the grounding pin.

[0024] In one example, the positive electrode pin 1 , the negative electrode pin 2 , and the ground pin 3 are arranged in parallel or independently.

[0025] In one example, the overall length of the metal housing is 3 mm to 10 mm; the length of each pin is 5 mm to 30 mm.

[0026] In this embodiment, the basic structure of the photodiode is similar to that of an ordinary diode, and is generally composed of a PN junction or a PIN junction. Unlike the PN junction, the PIN junction is a special form of PN junction formed by deliberately adding a thicker intrinsic layer (I-type layer) between the P-type semiconductor and the N-type semiconductor. Although the PN junction and the PIN junction are similar in structure, they are different in terms of space charge, barrier capacitance, barrier height, conductive mechanism, forward voltage drop, operating voltage and photosensitivity. In the application process, the type of photoelectric junction should be selected in combination with actual needs. In terms of working principle: an ordinary diode is in a conducting state under the action of a forward voltage and in a cut-off state under the action of a reverse voltage, and can only pass a very weak reverse current; while the photodiode works under the action of a reverse voltage, the extremely weak reverse current when there is no light is called a dark current, and the reverse current that rapidly increases to tens of microamperes when there is light is called a photocurrent. The change in light intensity causes the change in the reverse current, that is, the optical signal is converted into an electrical signal, and it can exist in the circuit as a photoelectric sensor device. When there is light, photons carrying energy enter the PN junction and transfer energy to the bound electrons on the covalent bonds. When the energy of the bound electrons increases to a certain level, they break free from the covalent bonds and become photogenerated carriers. At the same time, electron-hole pairs are generated. The carriers drift under the action of reverse voltage, causing the reverse current to increase rapidly, and the degree of increase is proportional to the light intensity.

[0027] Furthermore, the metal shell specifically includes: a metal tube seat 4 and a metal tube cap 5; the metal tube cap 5 specifically includes: a metal cap body and a light-transmitting cap head.

[0028] Among them, the photoelectric junction is fixed on the metal tube seat 4; the metal tube cap 5 is fixed on the metal tube seat 4; the metal tube cap 5 and the metal tube seat 4 form a cavity; the photoelectric junction is fixed in the cavity; one end of the positive pin 1 passes through the metal tube seat 4 and is connected to one end of the photoelectric junction; one end of the negative pin 2 passes through the metal tube seat 4 and is connected to the other end of the photoelectric junction; one end of the ground pin 3 is connected to the metal tube seat 4.

[0029] In one example, the metal tube base 4 and the metal cap body are made of aluminum or copper.

[0030] In one example, the light-transmitting cap head is made of glass.

[0031] In one example, the light-transmitting cap head is in a flat or round shape.

[0032] In one example, the metal tube cap 5 is buckled onto the metal tube base 4 and fixed as a whole by an adhesive.

[0033] As a preferred implementation mode, Figure 2 As shown, an indicating protrusion 41 is provided on the metal tube holder 4, and the indicating protrusion 41 is used to indicate the positive pin 1 of the photodiode. The pin close to one end of the indicating protrusion 41 is the positive electrode. Taking the positive pin 1 as a reference, from right to left are the grounding pin 3 and the negative pin 2.

[0034] In summary, the electrically shielded photodiode provided in the embodiment of the utility model improves the basic structure of the existing photodiode, provides a ground pin connected to the metal housing, and fully utilizes the structure of the photodiode itself to achieve electrical shielding.

[0035] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0036] This article uses specific examples to illustrate the principle and implementation of the utility model. The above examples are only used to help understand the structure and core idea of ​​the utility model. At the same time, for those skilled in the art, according to the idea of ​​the utility model, there will be changes in the specific implementation and application scope. In summary, the content of this specification should not be understood as limiting the utility model.

Claims

1. An electrically shielded photodiode, characterized in that include: A photoelectric junction, a positive electrode pin, a negative electrode pin, a ground pin and a metal shell; the photoelectric junction is a PN junction or a PIN junction; The photoelectric junction is fixed inside the metal shell; the photoelectric junction is used to convert the optical signal into an electrical signal under the condition of conduction; One end of the positive electrode pin passes through the metal shell and is connected to one end of the photoelectric junction; one end of the negative electrode pin passes through the metal shell and is connected to the other end of the photoelectric junction; one end of the grounding pin is connected to the metal shell; The metal shell is used to achieve electrical shielding of the photoelectric junction through the ground pin.

2. The electrically shielded photodiode according to claim 1, characterized in that The metal shell specifically includes: a metal tube seat and a metal tube cap; The metal tube cap is fixed on the metal tube seat; the metal tube cap and the metal tube seat form a cavity; the photoelectric junction is fixed in the cavity; one end of the positive pin passes through the metal tube seat and is connected to one end of the photoelectric junction; one end of the negative pin passes through the metal tube seat and is connected to the other end of the photoelectric junction; one end of the ground pin is connected to the metal tube seat.

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