Narrow and low-light-loss laser optical module

Abstract

The utility model relates to a narrowed and low-light-loss laser optical module. The narrowed and low-light-loss laser optical module comprises a base which is provided with a laser diode and a light detection diode; wherein the pipe diameter of the bottom of the necking-down long pipe is smaller than that of the base, the necking-down long pipe wraps the outer periphery of the fixing base so that the necking-down long pipe can be arranged on the surface of the base, and the upper portion of the necking-down long pipe is arranged to be in a straight-through hole shape without a cover body; the optical lens is arranged above the straight-through hole and is fixed on the bearing surface of the straight-through hole so as to directly form the narrow laser optical module; and the height of the necking long tubular shell is set according to the optical characteristics of the optical lens and the focal length required by the narrow laser optical module. Therefore, the necking-down long tubular shell and the optical lens are simultaneously a TO-CAN packaging cover and an outer shell for adjusting the optical focal length, so that the structure has the benefits that the manufacturing process is convenient and fast, the light loss can be reduced, the size is reduced and narrowed, and the structure can be accommodated in a light and thin electronic device.

Description

Technical Field

[0001] The utility model relates to a laser optical module, in particular to a laser optical module which has the advantages of convenient manufacturing process, reduced light loss, and smaller and narrower volume. Background Art

[0002] Since its advent, laser diodes (LDs) have been used in many fields such as optical communications, optical recording and optical storage. Laser diodes (LDs) are of two types: edge-emitting and surface-emitting. Surface-emitting LDs must be packaged to prevent dust from entering and eliminate the impact of ambient temperature changes on their performance, in order to ensure the stability of the product.

[0003] Secondly, the existing LD packaging method adopts the TO-CAN structure, which is as follows Figure 1A , 1B As shown, the LD package includes: a base 11, a plurality of electrical connection terminals 12, a light detector 13, a laser 14, a package cover 15, a light exit hole 151 on the top surface thereof, and a protective glass 16 for sealing the light exit hole 151 to prevent dust from entering. In this way, the LD package forms a laser light spot emitter 10a, and the laser beam L can be projected from the protective glass 16 above the package cover 15. However, the protective glass 16 needs to be pushed up from the bottom of the package cover 15 to the bottom of the light exit hole 151 and then bonded and fixed before packaging, which is inconvenient and time-consuming in the manufacturing process.

[0004] The laser spot emitter 10a mentioned above has the function of emitting a laser beam L. When the laser beam reaches the application end, Figure 2A , 2B As shown, it is necessary to encapsulate the outer shell 10b, and the front end of the outer shell 10b is provided with an optical lens 17 to form a laser optical module 10 with the required optical function. However, it is found that the outer shell 10b of the existing laser optical module 10 is installed on the periphery of the base 11. In the above-mentioned light source structure, the working distance between the laser 14 and the optical lens 17 (such as a collimator) is specific and requires high accuracy, thereby increasing the process and assembly costs. In addition, the laser optical module 10 needs to be encapsulated with the outer shell 10b, and its diameter (D4) is much larger than the base diameter (D1) of the laser light spot emitter 10a, so that the overall length or thickness is also considerable. For example, for the most commonly used 5.6mmφ specification of TO-CAN, the diameter (D2) of the encapsulation cap 15 is about 4 to 4.5mmφ, and the diameter (D1) of the base 11 is 5.6mm. In this way, the base 11 plus the outer shell 10b is at least 10mmφ, so the volume becomes fat and occupies space. Therefore, it is difficult to accommodate in a thin and light mobile device. Moreover, after the laser beam L passes through the first layer of protective glass 16, it is projected to the second layer of optical lens 17, which needs to pass through two layers of material and will cause light loss. These are all its shortcomings.

[0005] In view of the above problems, the inventors of the present invention have actively studied and improved the present invention, with solving the above deficiencies as the main subject. Utility Model Content

[0006] The main technical problem to be solved by the present invention is to overcome the above-mentioned defects of the prior art and provide a narrow and low light loss laser optical module, which has the advantages of convenient manufacturing process, reduced light loss, smaller and narrower volume, and thus can be accommodated in thin and light electronic devices.

[0007] The technical solution adopted by the utility model to solve its technical problems is:

[0008] A narrow and low light loss laser optical module comprises: a base, which is configured as a lead frame structure of a TO-CAN package, and has a plurality of electrical connection terminals extending downward; a laser diode, which is disposed on a primary fixing seat of the base; and a photodetector diode, which is located on a light emitting surface of the laser diode and is used to detect laser power; wherein:

[0009] A tapered long tube, the tube diameter of the upper half of which is smaller than the tube diameter of the lower half, and the tube diameter of the bottom of the tapered long tube is smaller than the base, and covers the outer periphery of the fixing seat so that it is arranged on the surface of the base, and the top of the tapered long tube is arranged in a straight-through opening type without a cover, and its overall height is greater than the packaging cover of the traditional TO-CAN structure, and a receiving surface is formed on the inner wall of the top end of the straight-through opening; an optical lens is inserted from the top of the straight-through opening and fixed on the receiving surface, so that the installation of the optical lens will not cause the tapered long tube to interfere with the base and the laser beam emitted by the laser diode, so as to directly form a narrow laser optical module; and the height of the tapered long tube is set according to the optical characteristics of the optical lens and the focal length required by the narrow laser optical module.

[0010] According to the above-mentioned features, the optical lens includes a diffractive optical lens or an optical lens.

[0011] According to the aforementioned features, the cross section of the receiving surface may be L-shaped, so as to support the optical lens and fix it on the top port of the straight opening.

[0012] According to the above-mentioned features, the diameter of the upper half of the tapered long tube is between 0.6 and 0.8 of the diameter of the lower half.

[0013] According to the above-mentioned features, the height of the tapered long tube is 7 to 12 mm.

[0014] With the help of the above-mentioned technical means, the long tube of the utility model is combined with an optical lens, which is also the packaging cover of the TO-CAN and the outer shell for adjusting the optical focal length. It has the advantages of convenient manufacturing process, reduced light loss, and smaller and narrower volume, so that it can be accommodated in a thin and light electronic device.

[0015] The beneficial effects of the utility model are that it has a convenient manufacturing process, can reduce light loss, and can make the volume smaller and narrower, thereby being able to be accommodated in a light and thin electronic device. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] The utility model is further described below in conjunction with the accompanying drawings and embodiments.

[0017] Figure 1A This is a three-dimensional diagram of the appearance of a conventional LD ​​package.

[0018] Figure 1B It is a cross-sectional view of a conventional LD ​​package.

[0019] Figure 2A It is an exploded perspective view of a conventional laser spot emitter and a housing.

[0020] Figure 2B The utility model is a combined cross-sectional view of an existing laser light spot emitter and a housing.

[0021] Figure 3 It is an exploded perspective view of a preferred embodiment of the utility model.

[0022] Figure 4 It is a combined sectional view of a preferred embodiment of the utility model.

[0023] Figure 5 It is a comparative schematic diagram of the utility model and the prior art.

[0024] Description of the numbers in the figure:

[0025] 20 Base

[0026] 21. Connecting terminal

[0027] 22 Laser diode

[0028] 221 Fixed seat

[0029] 23 Photodetector diode

[0030] 30 Narrow-mouthed long tube

[0031] 30a Upper half

[0032] 30b Lower half

[0033] 31 straight opening

[0034] 32 Surface

[0035] 40 Optical lenses

[0036] 50 Narrow Laser Optical Module DETAILED DESCRIPTION

[0037] The following is a description of the implementation of the present invention by means of specific embodiments. People skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied by means of other different specific embodiments, and the details in this specification can also be modified and changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0038] First, see Figure 3 to Figure 5 As shown, a preferred embodiment of the present invention comprises: a base 20, the base 20 is configured as a lead frame structure of a TO-CAN package, and a plurality of electrical connection terminals 21 are extended downward; a laser diode 22 is disposed on a fixing base 221 above the base 22; a photodetector diode 23 is located on the light emitting surface of the laser diode 22, and is used to detect the laser power; however, it is found that the above-mentioned structure belongs to the prior art, which is not the patent purpose of the present invention, and it is not repeated.

[0039] The utility model is mainly characterized in that: the tube diameter (D3) of the upper half 30a of the constricted long tube 30 is smaller than the tube diameter (D2) of the lower half 30b, and the tube diameter (D2) of the bottom of the constricted long tube 30 is smaller than the base 20, and covers the outer periphery of the fixing seat 221, so that it is arranged on the surface of the base 20, and the top of the constricted long tube 30 is arranged in the form of a straight through opening 31 without a cover body, and its overall height is greater than the packaging cover body of the traditional TO-CAN structure, and a receiving surface 32 is formed on the inner wall of the top end of the straight through opening 31; in this embodiment, the tube diameter (D3) of the upper half 30a of the constricted long tube 30 is between 0.6 and 0.8 of the tube diameter (D2) of the lower half 30b.

[0040] The optical lens 40 is inserted from above the straight opening 31 and fixed on the receiving surface 32. Since the diameter of the optical lens 40 (slightly smaller than D3) does not need to be as large as the diameter (D2) of the bottom of the tapered long tube 30, the straight opening 31 can be smaller than the diameter (D2) of the bottom of the tapered long tube 30, and it only needs to be slightly larger than the diameter of the optical lens 40 for its installation. In this way, the straight opening 31 of the upper half 30a of the tapered long tube 30 can be used to allow the optical lens 40 to be inserted and fixed, and the The diameter (D2) of the lower half 30b can be just placed on the base 20 and cover the outer periphery of the fixing base 221, so the installation of the optical lens 40 will not cause the tapered long tube 30 to interfere with the base 20 and the laser beam (L) emitted by the laser diode 22; however, the volume can be effectively reduced to directly form a narrow laser optical module 50; furthermore, the height (H) of the tapered long tube 30 is set according to the optical characteristics of the optical lens 40 and the focal length required by the laser optical module 50. In this embodiment, the optical lens 40 includes a diffractive optical lens or an optical lens.

[0041] In this embodiment, the cross section of the receiving surface 32 may be L-shaped, so as to support the optical lens 40 and fix it on the top end of the through opening 31 .

[0042] According to the above features, for the entire narrow laser optical module 50 of the utility model, the existing housing 10b and protective glass 16 are omitted, and the long tube 30 plus the optical lens 40 is used as the packaging cover of the TO-CAN and the outer shell for adjusting the optical focal length, so the manufacturing process is convenient, and the material and assembly costs of the entire module are reduced. It can also reduce light loss, make the volume smaller and narrower, and thus can be accommodated in a thin and light electronic device.

[0043] Please refer to Figure 5As shown, the schematic diagram comparing the present invention with the prior art, the current specifications of TO-CAN are: 3.8mmφ, 5.6mmφ, 9.0 mmφ. For example, if the diameter (D1) of the base 11 of the most commonly used prior art is 5.6mmφ, then with the shell 10b, it will be at least 10mmφ, thus making the volume fat and occupying space. On the other hand, the diameter (D1) of the base 20 of the present invention is also 5.6mmφ, the diameter (D2) of the lower half 30b of the tapered long tube 30 is about 4 to 4.5mmφ, the diameter (D3) of the upper half 30a is about 2.5 to 3.5mmφ, and the height (H) can be set according to the optical characteristics of the optical lens 40 and the focal length required by the laser optical module 50, so it can be about 7 to 12mm, but it is not limited to this. As a result, the volume of the laser optical module 50 of the present invention is reduced by at least several times compared to the laser optical module 10 of the prior art, thereby making the laser optical module 50 narrower as a whole and more suitable for thin and light mobile devices or electronic devices.

[0044] The utility model has the following effects that need to be further explained:

[0045] 1. The narrow laser optical module 50 of the present invention does not have the packaging cover 15, protective glass 16 and housing 10b of the prior art. The protective glass 16 of the prior art must be pushed upward from the bottom of the packaging cover 15 to the bottom of the light outlet 151 and then glued and fixed before packaging, which is inconvenient and time-consuming in the manufacturing process. The present invention only uses the long tube 30 plus the optical lens 40, which is both the packaging cover of the TO-CAN and the outer shell for adjusting the optical focal length. Therefore, the manufacturing process is convenient, which not only reduces the material and assembly costs of the entire module, but also has the effect of reducing light loss.

[0046] 2. The optical lens 40 of the utility model is inserted from above the straight opening 31 of the long tube 30 and fixed on the receiving surface 32. It is not only easy to assemble, but also when the height (H) of the long tube 30 is set according to the desired focal length, the height of the optical lens 40 will be accurately positioned, and the accurate focal length can be obtained.

[0047] 3. The narrow laser optical module 50 of the present invention is at least several times smaller in volume than the laser optical module 10 of the prior art, thereby making it narrower overall and more suitable for use in thin and light mobile devices or electronic devices, and having a wider range of uses.

[0048] The above description is only a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention still fall within the scope of the technical solution of the present invention.

Claims

1. A narrow and low light loss laser optical module, characterized in that: include: A base, which is configured as a lead frame structure of a TO-CAN package and has a plurality of electrical connection terminals extending downward; A laser diode is arranged on a fixed seat above the base; A photodetector diode, located on the light-emitting surface of the laser diode, for detecting the laser power; It is characterized by: A constricted long tube, the diameter of the upper half of which is smaller than that of the lower half, and the diameter of the bottom of the constricted long tube is smaller than that of the base, and covers the outer periphery of the fixing base, so that it is arranged on the surface of the base, and the upper part of the constricted long tube is arranged in a straight through opening type without a cover body, and its overall height is greater than the packaging cover body of the traditional TO-CAN structure, and a receiving surface is formed on the inner wall of the top end of the straight through opening; An optical lens is placed above the through opening and fixed on the receiving surface, so that the installation of the optical lens will not cause the narrowed long tube to interfere with the base and the laser beam emitted by the laser diode, so as to directly form a narrow laser optical module; and The height of the tapered long tube is set according to the optical properties of the optical lens and the focal length required by the narrow laser optical module.

2. The narrowed and low light loss laser optical module according to claim 1, characterized in that: The optical lens comprises a diffractive optical lens or an optical lens.

3. The narrowed and low light loss laser optical module according to claim 1, characterized in that: The cross section of the receiving surface is L-shaped, which is used to support the optical lens and fix it on the top port of the straight-through opening.

4. The narrowed and low light loss laser optical module according to claim 1, characterized in that: The diameter of the upper half of the narrowed long tube is between 0.6 and 0.8 of the diameter of the lower half.

5. The narrowed and low light loss laser optical module according to claim 4, characterized in that: The height of the narrowed long tube is 7 to 12 mm.

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