High-coupling-efficiency aspheric lens for shaping 510nm-535nm laser light source and light source coupling module

Abstract

The invention discloses an aspherical lens with high coupling efficiency for shaping a 510nm-535nm laser light source and a light source coupling module, the aspherical lens sequentially comprises a front surface, a side surface and a rear surface from a light emitting end to a light receiving end, and the aspherical lens is used for shaping a laser light source with the wavelength of 510-535nm, the size of a light emitting surface of 2 mu m * 6 mu m and the light emitting surface of 510-535nm. Laser with the divergence angle Y direction being 22.5 degrees and the divergence angle X direction being 6.3 degrees of emergent light beams is converged into 9.0 mu m * 3 mu m light spots at a light receiving end 4.88 mm away from a light emitting end, the light spots are coupled with a single-mode optical fiber with the vertical aperture NA being 0.15, and conical light beams with the light emitting area being 9 mu m and the light emitting angle being 17 degrees are formed after the light beams are transmitted through the single-mode optical fiber. The light source coupling module comprises the aspheric lens, the optical axis of the aspheric lens, the light-emitting chip of the green laser tube and the fiber core of the single-mode optical fiber are aligned with the packaging line of the module, and one end of the green laser tube, one end of the aspheric lens and one end of the optical fiber are packaged in a packaging shell. According to the high-coupling-efficiency aspherical lens for 510-535 nm laser light source shaping and the light source coupling module, it can be guaranteed that light spots at the output end are circle center light spots, energy distribution is uniform, and brightness is uniform.

Description

Technical Field

[0001] The present invention relates to the field of optical communication technology, and in particular to an aspheric lens, and more particularly to an aspheric lens with high coupling efficiency and a light source coupling module for shaping a 510nm-535nm laser light source. Background Art

[0002] In the existing measurement and mapping industries, by shaping the 510nm-535nm laser light source (referred to as green light) into a circular spot, it is widely used in measurement, mapping, medical and other industries that have high requirements for the light spot and line quality of the light source.

[0003] Green light (510nm-535nm) LD lasers are used as direct light sources, which are then focused by lenses and split into points and lines. Since 510nm-535nm LD lasers use edge-emitting semiconductor process technology (EEL), compared to vertical-cavity surface-emitting lasers (VCSELs), edge-emitting semiconductor lasers are more mature in technology development and have advantages such as a wide wavelength range, high electro-optical conversion efficiency, and high power, so they are widely used in the market. However, due to the process characteristics of edge-emitting semiconductor lasers, the vertical divergence angle is much larger than the horizontal divergence angle, thus forming an elliptical light spot.

[0004] In applications, especially in the surveying and mapping tool industry, when an elliptical spot is converted into a line, there will be uneven energy distribution and localized darkening of the laser line. Users will feel a significant change, which will affect the application experience. Summary of the Invention

[0005] The technical problem to be solved by the present invention is: in order to solve the technical problems in the prior art that, after the elliptical light spot is converted into a line, there will be uneven energy distribution and local dark laser lines. The present invention provides a high-coupling-efficiency aspheric lens and a light source coupling module for shaping a 510nm-535nm laser light source, which can ensure that the light spot at the output end is a circular center spot with uniform energy distribution and uniform brightness.

[0006] The technical solution adopted by the present invention to solve its technical problems is: a high-coupling-efficiency aspheric lens for shaping a 510nm-535nm laser light source, wherein the aspheric lens has a front surface, a side surface, and a rear surface from the light emitting end to the light receiving end. The aspheric lens converges a laser with a wavelength of 510-535nm, a light-emitting surface size of 2μm×6μm, and an output beam divergence angle of 22.5° in the Y direction and 6.3° in the X direction at a light receiving end 4.88mm away from the light emitting end into a 9.0μm×3μm light spot, which is coupled to a single-mode optical fiber with a vertical aperture NA=0.15. After transmission through the single-mode optical fiber, the laser is formed into a conical beam with a light-emitting area of 9μm and a light-emitting angle of 17°.

[0007] The front surface and the back surface are both aspherical surfaces, and the surface shape is an even-order aspherical surface with the highest order of 10, and the equation is:

[0008]

[0009] Where C = 1 / R;

[0010] Where Z (r) Taking the intersection of each aspheric surface and the optical axis as the starting point, along the axial value of the optical axis, k is the cone coefficient, c is the center curvature of the mirror, R = 1 / C is the curvature radius of the mirror, r is the vertical axis height of a point on the mirror, A2, A4, A6, A8, A 10 is the coefficient of the higher-order term in the aspheric formula, and the coefficient values are as follows:

[0011] Aspheric coefficients A2, A4, A6, A8, A 10 The value of:

[0012] r k <![CDATA[A2]]> <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 <!-- 1 -->]]> front surface 2 -3.45692 0 -0.09092 0.04276 0 0 front surface -1.06807 -0.87122 0 0.08074 -0.03886 0.01623 0

[0013] The invention uses a high-coupling-efficiency aspheric lens for shaping 510nm-535nm laser light sources. The light source with a specific wavelength, luminous surface, and output beam divergence angle is coupled to a single-mode optical fiber through the aspheric lens to form a conical beam with a specific luminous area and luminous angle.

[0014] Furthermore, the front surface is a front convex aspheric surface, the rear surface is a rear convex aspheric surface, and the side surface is a cylindrical surface with a diameter of 2.5 mm.

[0015] Furthermore, the distance between the vertex of the front surface and the vertex of the back surface is the center thickness of the lens, which is 1.3±0.02 mm.

[0016] Furthermore, the light-clearing aperture of the front surface is 1.2 mm, and the light-clearing aperture of the rear surface is 1.6 mm.

[0017] Furthermore, the lens is made of D-ZLaF50 glass, and its refractive index is 1.8 for a light beam with a wavelength of 510-535 nm.

[0018] Furthermore, a protective glass is provided between the front surface and the light emitting end, the distance between the protective glass and the vertex of the front surface is 0.74 mm, and the thickness of the protective glass is 0.3 mm.

[0019] The technical solution adopted by the present invention to solve its technical problem is: a light source coupling module, including the above-mentioned aspheric lens, the optical axis of the aspheric lens, the light-emitting chip of the green laser tube, and the core of the single-mode optical fiber are aligned with the packaging line of the module, and the green laser tube, the aspheric lens and one end of the optical fiber are encapsulated in a packaging shell.

[0020] Furthermore, the aspheric lens, the single-mode optical fiber and the packaging shell are connected by dispensing glue.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] 1. The present invention provides a high-coupling-efficiency aspheric lens and light source coupling module for shaping a 510nm-535nm laser light source. The aspheric lens couples light emitted by a green laser tube into a single-mode optical fiber. The laser, which has an emission wavelength of 510-535nm, a luminous area of 2μm×6μm, and an output beam divergence angle (FWHM) of 22.5° in the Y direction and 6.3° in the X direction, is focused at a receiving end face 4.88mm away from the light-emitting chip into a 9.0μm×3μm light spot. The light spot is coupled to a single-mode optical fiber with a numerical aperture NA=0.15, achieving a theoretical efficiency of 89% and an experimental maximum coupling efficiency of 85%.

[0023] 2. The present invention is used for a high-coupling-efficiency aspheric lens and a light source coupling module for shaping a 510nm-535nm laser light source. The aspheric lens, the green laser tube and the green laser tube are packaged to form a light source coupling module, which has a small structure and is easy to assemble. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described below with reference to the accompanying drawings and examples.

[0025] Figure 1 This is the green light shaping coupling and converging optical path diagram of the present invention;

[0026] Figure 2 Schematic diagram of the structure of an aspheric lens;

[0027] Figure 3 This is the installation diagram of the green light shaping, coupling and converging light source coupling module;

[0028] Figure 4 It is the light spot diagram at the light receiving point;

[0029] In the figure: 1. Light emitting end, 2. Aspheric lens, 21. Front surface, 22. Side surface, 23. Back surface, 3. Light receiving end, 4. Single-mode optical fiber, 5. Green laser tube, 51. Light-emitting chip, 6. Package shell, 7. Protective glass. DETAILED DESCRIPTION

[0030] The present invention will now be described in further detail with reference to the accompanying drawings, which are simplified schematic diagrams that illustrate the basic structure of the present invention in a schematic manner.

[0031] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, features defined as "first" or "second" may explicitly or implicitly include one or more of such features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0032] In the description of the present invention, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," and "connected" should be understood in a broad sense. For example, they may refer to fixed, detachable, or integral connections; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components. Those skilled in the art will understand the specific meanings of the above terms in the present invention based on the specific circumstances.

[0033] like Figure 1 Figure 2 shows a high-coupling-efficiency aspheric lens for shaping 510nm-535nm laser sources. The aspheric lens 2 comprises a front surface 21, a side surface 22, and a rear surface 23, from the light emitting end 1 to the light receiving end 3. Aspheric lens 2 focuses laser light with a wavelength of 510-535nm, a 2μm x 6μm emitting surface, and an outgoing beam divergence of 22.5° in the Y direction and 6.3° in the X direction. This lens converges the laser light into a 9.0μm x 3μm spot at the light receiving end, 4.88mm from the light emitting end. This spot is coupled to a single-mode fiber 4 with a vertical aperture (NA) of 0.15. Theoretical coupling efficiency is 89%, and the experimental maximum coupling efficiency is 85%. After transmission through the single-mode fiber, the beam is formed into a conical beam with a 9μm emitting area and a 17° emitting angle. After passing through a 10mm collimator, the conical beam forms a collimated beam with a divergence of 0.9mrad, resulting in a spot size of φ5.5mm at a distance of 6m.

[0034] The front surface 21 and the back surface 23 are both aspherical surfaces, and their surface shapes are expressed using the highest 10th-order even-order aspherical surface equation:

[0035]

[0036] Where C = 1 / R;

[0037] Where Z(r) Taking the intersection of each aspheric surface and the optical axis as the starting point, along the axial value of the optical axis, k is the cone coefficient, c is the center curvature of the mirror, R = 1 / C is the curvature radius of the mirror, r is the vertical axis height of a point on the mirror, A2, A4, A6, A8, A 10 is the coefficient of the higher-order term in the aspheric formula, and the coefficient values are as follows:

[0038] Aspheric coefficients A2, A4, A6, A8, A 10 The value of:

[0039] r k <![CDATA[A2]]> <![CDATA[A4]]> <![CDATA[A6]]> <![CDATA[A8]]> <![CDATA[A 10 ]]> front surface 2 -3.45692 0 -0.09092 0.04276 0 0 rear surface -1.06807 -0.87122 0 0.08074 -0.03886 0.01623 0

[0040] like Figure 3 As shown, specifically, the front surface 21 is a front convex aspheric surface, the rear surface 23 is a rear convex aspheric surface, and the side surface 22 is a cylindrical surface with a diameter of 2.5 mm.

[0041] The distance between the vertex of the front surface 21 and the vertex of the back surface 23 is the center thickness of the lens, which is 1.3±0.02 mm.

[0042] Preferably, the light-clearing diameter of the front surface 21 is 1.2 mm, and the light-clearing diameter of the rear surface 23 is 1.6 mm.

[0043] Preferably, the lens is made of D-ZLaF50 glass, and its refractive index is 1.8 for a light beam with a wavelength of 510-535 nm.

[0044] Preferably, a protective glass 7 is provided between the front surface 21 and the light emitting end 1 , the distance between the protective glass 7 and the vertex of the front surface 21 is 0.74 mm, and the thickness of the protective glass 7 is 0.3 mm.

[0045] like Figure 4 As shown in the figure, it can be seen that the shape of the light spot is consistent with the shape of the light-emitting surface, and most of the light falls within the diameter of the optical fiber core.

[0046] like Figure 3 As shown, a light source coupling module includes the aforementioned aspheric lens 2. The optical axis of the aspheric lens 2, the light-emitting chip 51 of the green laser tube 5, and the core of the single-mode optical fiber 4 are aligned with the module's packaging line. The green laser tube 5, the aspheric lens 2, and one end of the single-mode optical fiber are encapsulated within an encapsulation shell 6. The aspheric lens 2, the single-mode optical fiber, and the encapsulation shell are connected by dispensing glue.

[0047] The specific sealing process is as follows: Align the light-emitting chip in the green laser tube 1 with the optical axis (X-axis) of the aspheric lens 2, and align the core of the single-mode fiber with the module's packaging line. Fix the laser tube 1 or coupling lens 2, move the coupling lens or laser tube to keep the optical axes aligned, and secure with glue. Move the single-mode fiber to the focusing point to ensure that the focused light can fully enter the fiber, and then secure the fiber with glue.

[0048] The aspheric lens 2 focuses the laser light emitted by the LD (510-535nm wavelength), with a 2μm x 6μm luminous area and an output beam divergence (FWHM) of 22.5° in the Y direction and 6.3° in the X direction) at the receiving end face, located 4.88mm from the light-emitting chip, into a 9.0μm x 3μm spot. This spot is coupled to a single-mode fiber with a numerical aperture (NA) of 0.15, achieving a theoretical efficiency of 89% and an experimental maximum coupling efficiency of 85%. After transmission through the single-mode fiber, the beam is formed into a conical beam with a 9μm luminous area and a 17° beam angle. After passing through an f10mm collimator, the beam is collimated with a divergence angle of 0.9mrad, resulting in a spot size of φ5.5mm at a distance of 6m. The structure is compact and easy to assemble.

[0049] In summary, the present invention provides an aspheric lens with high coupling efficiency and a light source coupling module for shaping a 510nm-535nm laser light source. The aspheric lens couples light emitted by a green laser tube into a single-mode optical fiber.

[0050] The above description is intended to serve as a guide for the preferred embodiments of the present invention. Based on the above description, relevant personnel are fully capable of making various changes and modifications without departing from the technical scope of the present invention. The technical scope of the present invention is not limited to the contents of the specification and must be determined according to the scope of the claims.

Claims

1. A high-coupling-efficiency aspheric lens for shaping 510nm-535nm laser light sources, characterized in that: The aspheric lens (2) is sequentially composed of a front surface (21), a side surface (22), and a rear surface (23) from the light emitting end (1) to the light receiving end (3). The aspheric lens (2) converges a laser beam having a wavelength of 510-535 nm, a light emitting surface size of 2 μm×6 μm, and an outgoing light beam divergence angle of 22.5° in the Y direction and 6.3° in the X direction into a light spot of 9.0 μm×3 μm at the light receiving end (3) which is 4.88 mm away from the light emitting end (1). The laser beam is coupled with a single-mode optical fiber (4) having a vertical aperture NA=0.15, and after being transmitted through the single-mode optical fiber (4), a conical light beam is formed with a light emitting area of 9 μm and a light emitting angle of 17°. The front surface (21) and the back surface (23) are both aspherical surfaces, and their surface shapes are even-order aspherical surfaces with the highest order of 10, and the equation is: Where C = 1 / R; Where Z (r) Taking the intersection of each aspheric surface and the optical axis as the starting point, along the axial value of the optical axis, k is the cone coefficient, c is the center curvature of the mirror, R = 1 / C is the curvature radius of the mirror, r is the vertical axis height of a point on the mirror, A2, A4, A6, A8, A 10 is the coefficient of the higher-order term in the aspheric formula, and the coefficient values are as follows: Aspheric coefficients A2, A4, A6, A8, A 10 The value of: 。 2. The aspheric lens with high coupling efficiency for shaping 510nm-535nm laser light sources according to claim 1, characterized in that: The front surface (21) is a front convex aspheric surface, the rear surface (23) is a rear convex aspheric surface, and the side surface (22) is a cylindrical surface with a diameter of 2.5 mm.

3. The aspheric lens with high coupling efficiency for shaping 510nm-535nm laser light sources according to claim 1, characterized in that: The distance between the vertex of the front surface (21) and the vertex of the back surface (23) is the center thickness of the lens, which is 1.3±0.02 mm.

4. The aspheric lens with high coupling efficiency for shaping a 510nm-535nm laser light source according to claim 1, characterized in that: The light-clearing aperture of the front surface (21) is 1.2 mm, and the light-clearing aperture of the rear surface (23) is 1.6 mm.

5. The aspheric lens with high coupling efficiency for shaping 510nm-535nm laser light sources according to claim 1, characterized in that: The lens is made of D-ZLaF50 glass, and its refractive index is 1.8 for a light beam with a wavelength of 510-535 nm.

6. The aspheric lens with high coupling efficiency for shaping a 510nm-535nm laser light source according to claim 1, characterized in that: A protective glass (7) is provided between the front surface (21) and the light emitting end (1); the distance between the protective glass (7) and the vertex of the front surface (21) is 0.74 mm; and the thickness of the protective glass (7) is 0.3 mm.

7. A light source coupling module, characterized in that: The aspheric lens comprises the aspheric lens according to any one of claims 1 to 6, wherein the optical axis of the aspheric lens (2), the light-emitting chip of the green laser tube (5), the core of the single-mode optical fiber (4) and the packaging line of the module are aligned, and the green laser tube (5), the aspheric lens and one end of the single-mode optical fiber (4) are packaged in a packaging shell (6).

8. The light source coupling module according to claim 1, wherein: The aspheric lens, the single-mode optical fiber (4) and the packaging shell (6) are connected by dispensing glue.

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