Optical path system for a laser beam lamp

Abstract

A light path system for a laser beam lamp, comprising a laser light source, an imaging object and an imaging lens arranged in sequence, the imaging lens comprising: a first lens group comprising a first lens with negative focal length and a second lens with positive focal length arranged in sequence, the first lens and the second lens being dry bonded, the second lens being a spherical double convex lens; a magnifying lens coaxial with the first lens group and fixedly mounted in the light emitting direction of the first lens group; the first lens is a non-spherical double concave lens, and the magnifying lens is a spherical double convex lens; the total optical length TTL of the imaging lens is less than 150 mm.

Description

Technical Field

[0001] This utility model relates to the field of stage lighting technology, and more specifically, to an optical path system for a laser beam light. Background Technology

[0002] In existing technologies, laser beam lamp imaging lenses typically have a dual-lens structure. The first lens group expands the beam using a magnifying lens, while the second lens group consists of three spherical lenses for collimation and focusing. Due to the inherent characteristics of spherical lenses, they exhibit spherical aberration and chromatic aberration, resulting in weak aberration correction capabilities. To compensate for the optical defects of spherical lenses, the imaging quality of the imaging lens needs to be improved by increasing the spacing between the lenses, leading to an increase in the total optical length of the imaging lens. The excessively long optical path makes it difficult to compress the size of the lamp, limiting the imaging lens to larger lamps and making it unsuitable for small and medium-sized lamps. Furthermore, the spherical lens has a single radius of curvature, resulting in weak aberration correction capabilities for complex optical paths, and is prone to blurring of the light spot edges in applications requiring high brightness output. Summary of the Invention

[0003] This invention provides an optical path system for a laser beam lamp, which solves the problems mentioned in the background art.

[0004] An optical path system for a laser beam lamp includes a laser source, an imaging object, and an imaging lens arranged in sequence. The imaging lens includes: The first lens group includes a first lens with negative optical power and a second lens with positive optical power arranged in sequence. The first lens and the second lens are dry-cemented together, and the second lens is a spherical biconvex lens. A magnifying lens is coaxial with the first lens group and fixedly installed in the light-emitting direction of the first lens group; The first lens is an aspherical biconcave lens, and the magnifying lens is a spherical biconvex lens; the total optical length (TTL) of the imaging lens is less than 150 mm.

[0005] As a further improvement of this utility model, the light-incident surface of the first lens is an even-order aspherical surface, and the radius of curvature of the cemented surface of the first lens and the second lens is -284mm; the radius of curvature of the light-exiting surface of the second lens is 51mm, the radius of curvature of the light-incident surface of the magnifying lens is -415mm, and the radius of curvature of the light-exiting surface of the magnifying lens is 138mm.

[0006] As a further improvement of this utility model, the thickness of the first lens is 2mm, the thickness of the second lens is 30mm, and the thickness of the magnifying lens is 20mm.

[0007] As a further improvement of this utility model, the total optical length of the imaging lens is 149mm.

[0008] As a further improvement of this utility model, the light emission angle of the imaging lens is 1.3°.

[0009] As a further improvement of this utility model, the first mirror group also includes a stepped pressure ring and a pressure ring, with the pressure ring sleeved and installed on the light-emitting end of the stepped pressure ring.

[0010] As a further improvement of this utility model, the first lens and the second lens are installed inside the stepped pressure ring, and the aperture of the first lens is smaller than that of the second lens.

[0011] As a further improvement to this utility model, F / #=1.18.

[0012] As a further improvement of this utility model, the light-emitting aperture of the imaging lens is 115mm.

[0013] As a further improvement of this utility model, it also includes a color plate disk located between the laser light source and the imaging object, the imaging object including but not limited to a fixed pattern disk or a cutting disk with multiple pattern pieces.

[0014] Compared with the prior art, the beneficial effects of this embodiment are as follows: (1) In this utility model, the imaging lens has three lenses. By using an aspherical lens as the first lens, the total optical length of the imaging lens can be effectively compressed while maintaining the imaging quality.

[0015] (2) In this embodiment, by adjusting the curvature radius and thickness of the first lens, the second lens and the magnifying lens, the light refraction angle of each lens is made more reasonable, which is conducive to further compressing the total optical length of the imaging lens while maintaining the imaging quality. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the optical path system of this utility model.

[0017] Figure 2 This is a dot diagram of the optical path system of this utility model.

[0018] Figure 3 This is a transverse optical sector diagram of the optical path system of this utility model.

[0019] In the diagram: 1-Laser source; 2-Color filter disk; 3-Imaging object; 4-Imaging lens; 41-First lens group; 411-First lens; 412-Second lens; 413-Stepped pressure ring; 414-Pressure ring; 42-Magnifying lens. Detailed Implementation

[0020] Combined with appendix Figure 1 To be continued Figure 3An optical path system for a laser beam lamp includes a laser light source 1, an imaging object 3, and an imaging lens 4 arranged in sequence. The laser light source 1 is a 50W laser light source. The imaging lens 4 includes a first lens group 41 and a magnifying lens 42. The first lens group 41 includes a first lens 411 with negative optical power and a second lens 412 with positive optical power arranged in sequence. The first lens 411 and the second lens 412 are dry-bonded. The first lens 411 is an aspherical biconcave lens, and the second lens 412 is a spherical biconvex lens. The magnifying lens 42 is coaxial with the first lens group 41 and is fixedly installed in the light-emitting direction of the first lens group 41. The magnifying lens 42 is a spherical biconvex lens. In this embodiment, the first lens group 41 and the magnifying lens 42 are located sequentially in the light-emitting direction of the laser light source 1. The first lens group 41 is used to converge the light emitted from the laser light source 1 to form a beam. The magnifying lens 42 is used to expand the beam emitted from the first lens group 41 so that the light is emitted at a certain emission angle to form a uniform light spot.

[0021] Traditional laser beam lights typically have a dual-lens structure with four lenses. Three lenses are cemented together to form one lens group, and all four lenses are spherical lenses. Therefore, the imaging quality of the imaging lens needs to be improved by increasing the distance between the two lens groups. This results in an excessively long optical length of the imaging lens, making it unsuitable for small and medium-sized lighting fixtures.

[0022] The imaging lens 4 of this invention uses an aspherical lens as its first lens 411, meaning the radius of curvature on the light-incident surface of the first lens 411 can continuously change. This allows all light rays passing through the first lens 411 to converge precisely at the same focal point, effectively reducing spherical aberration. Furthermore, by adjusting the conic coefficient to optimize the curvature distribution on the light-incident surface of the first lens 411, image edge blurring is eliminated. In this case, the aspherical nature of the first lens 411 is sufficient to correct the aberrations produced by the imaging lens 4, thus eliminating the need to reduce aberrations by increasing the distance between the magnifying lens 42 and the first lens group 41. Compared to traditional imaging lenses, the imaging lens 4 of this invention has a smaller overall optical length and fewer lenses, but its image quality is better than that of traditional imaging lenses.

[0023] That is, the total optical length (TTL) of the imaging lens 4 is less than 150mm. The total optical length is the distance from the light-emitting surface of the magnifying lens 42 to the image surface, which is the distance between the light-emitting surface of the magnifying lens 42 and the image object 3. At this time, the light emitted from the light source can form a clear and uniform light spot after passing through the imaging lens 4, and the imaging lens 4 can be used for small and medium-sized lamps.

[0024] The beneficial effect of this embodiment is that, compared with traditional imaging lenses, the imaging lens 4 of this utility model reduces the number of lenses, and by using an aspherical first lens 411, it can effectively compress the total optical length of the imaging lens 4, so that the total optical length TTL < 150mm, and can also ensure the imaging quality of the imaging lens 4.

[0025] As a new implementation method, combined with the appendix Figure 1 and attached Figure 2 The incident surface of the first lens 411 is an even-order aspherical surface, and the radius of curvature of the cemented surface of the first lens 411 and the second lens 412 is -284 mm; the radius of curvature of the emitting surface of the second lens 412 is 51 mm; the radius of curvature of the incident surface of the magnifying lens 42 is -415 mm, and the radius of curvature of the emitting surface of the magnifying lens 42 is 138 mm. The first lens 411, the second lens 412, and the magnifying lens 42 are arranged sequentially in the emitting direction of the laser source 1. The first lens 411 and the second lens 412 are dry-cemented to form a first lens group 41, and there is a certain distance between the first lens group 41 and the magnifying lens 42. As those skilled in the art will understand, the sign of the radius of curvature is used to indicate the concavity or convexity direction of the lens surface. For example, if the radius of curvature of the cemented surface of the first lens 411 is negative, the cemented surface of the first lens 411 is concave towards the light source; or, if the radius of curvature of the cemented surface of the second lens 412 is negative... The cemented surface of the second lens 412 bulges towards the laser source 1; the incident surface of the first lens 411 is an even-order aspherical surface. Compared with odd-order aspherical surfaces, even-order aspherical surfaces have more variations in the radius of curvature, which can better correct the aberrations of the imaging lens 4; the radius of curvature of the first lens 411 and the radius of curvature of the second lens 412 work together to facilitate the convergence of light emitted from the laser source 1 into a beam, reducing the exit angle of the light passing through the first lens group 41; the magnifying lens 42, used in conjunction with the first lens group 41, can expand the beam and further adjust the exit angle of the emitted light. The beneficial effect of this embodiment is that by adjusting the radii of curvature of the first lens 411, the second lens 412, and the magnifying lens 42, the imaging quality of the imaging lens 4 can be improved, and the overall optical length can be further reduced.

[0026] As a new implementation method, combined with the appendix Figure 1 To be continued Figure 3The thickness of the first lens 411 is 2mm, the thickness of the second lens 412 is 30mm, and the thickness of the magnifying lens 42 is 20mm. As will be understood by those skilled in the art, the total optical length (TTL) is generally defined as the distance from the light-emitting surface of the magnifying lens 42 to the image plane. With constant optical power, increasing the thickness of a single lens directly leads to an increase in the total optical length (TTL). The optical power of a lens is determined by its radius of curvature and thickness. Increasing the thickness allows for a flatter curvature while maintaining constant optical power. A flatter curvature produces fewer aberrations, thus improving the imaging quality of the imaging lens 4. The first lens 411 is an aspherical lens, primarily correcting aberrations through aspherical surfaces; therefore, the thickness of the first lens 411 is relatively small. The second lens 412 has a larger thickness, effectively converging light while correcting aberrations, thereby reducing the RMS spot radius of the image plane. The magnifying lens 42, through the combination of its thickness and radius of curvature, expands the light beam and adjusts the exit angle. The beneficial effect of this embodiment is that the thickness and radius of curvature of the first lens 411, the second lens 412, and the magnifying lens 42 are coordinated with each other, thereby improving the imaging quality of the imaging lens 4 by reducing the RMS spot radius of the image plane and compressing the total optical length of the imaging lens 4.

[0027] As a new implementation method, combined with the appendix Figure 1 The total optical length of the imaging lens 4 is 149mm. In this embodiment, the first lens 411 is an aspherical lens, and the thickness and radius of curvature of the first lens 411, the second lens 412, and the magnifying lens 42 are adjusted to compress the total optical length of the imaging lens 4 to 149mm. The total optical length of a conventional beam lamp lens is usually 170-180mm, and the RMS radius of its emitted light is usually 70mm. The imaging lens 4 of this invention differs from conventional beam lamp lenses in two ways: firstly, the total optical length of the imaging lens 4 of this invention is shortened; secondly, the RMS radius of the emitted light from the imaging lens 4 is 35mm, meaning that this invention can form a light spot with higher clarity and sharper edges. The beneficial effect of this embodiment is that when the total optical length of the imaging lens 4 is 149mm, the light passing through the imaging lens 4 can also form a clear light spot.

[0028] As a new implementation method, combined with the appendix Figure 1 The imaging lens 4 has an exit angle of 1.3°. The imaging lens 4 effectively collimates the light rays passing through it, reducing the exit angle to 1.3°. As those skilled in the art will understand, a smaller exit angle increases the propagation distance of the light; that is, the smaller the exit angle, the farther the light travels. The beneficial effect of this embodiment is that the light emitted from the laser source 1 can form an extremely narrow beam, and the beam projected onto the image plane can form a clear, sharp-edged light spot.

[0029] As a new implementation method, combined with the appendix Figure 1 The first lens assembly 41 also includes a stepped retaining ring 413 and a retaining ring 414, with the retaining ring 414 fitted onto the light-emitting end of the stepped retaining ring 413. The stepped retaining ring 413 has a concentric ring structure, and its light-incident end is also provided with a limiting part for limiting the first lens 411; the retaining ring 414 has a ring structure and is adapted to the stepped retaining ring 413; the outer surface of the stepped retaining ring 413 is also provided with mounting holes for fixing the first lens assembly 41 inside the lamp, and the first lens assembly 41 is fixedly installed inside the lamp through the mounting holes. The beneficial effect of this embodiment is that the stepped retaining ring 413 and the retaining ring 414 can fix the first lens assembly 41 in the light-emitting direction of the laser light source 1, preventing the first lens assembly 41 from shaking and affecting the light emission effect of the light passing through the imaging lens 4.

[0030] As a new implementation method, combined with the appendix Figure 1 The first lens 411 and the second lens 412 are installed inside the stepped pressure ring 413, with the aperture of the first lens 411 being smaller than that of the second lens 412. The stepped pressure ring 413 consists of two concentric rings with different diameters, the diameter of its light-incident end being smaller than that of its light-outcident end; the first lens 411 is installed at its light-incident end, and the second lens 412 is installed at its light-outcident end; the radius of curvature of the light-outcident surface of the first lens 411 is the same as that of the light-incident surface of the second lens 412, and the first lens 411 and the second lens 412 are dry-glued together; since the light emitted from the laser source 1 needs to pass through the first lens 411 and the second lens 412 in sequence, the smaller aperture of the first lens 411 than the second lens 412 ensures that all the light emitted from the first lens 411 enters the second lens 412 and exits from the second lens 412. The beneficial effect of this embodiment is that the first lens 411 and the second lens 412 are installed in the stepped pressure ring 413, which can prevent the first lens 411 and the second lens 412 from becoming eccentric due to relative displacement, thus affecting the light output effect of the imaging lens 4.

[0031] As a new implementation method, combined with the appendix Figure 1 F / # = 1.18. F / # is the aperture coefficient, which, as those skilled in the art will understand, is the ratio between the system's focal length and the entrance pupil diameter. When F / # = 1.18, most light rays can enter the optical path system and form a clear and sharp beam through the imaging lens 4. The beneficial effect of this embodiment is that F / # = 1.18 ensures the light flux entering the optical path system, guaranteeing that the light rays emitted from the imaging lens 4 can form a bright beam.

[0032] As a new implementation method, combined with the appendix Figure 1The imaging lens 4 has an output aperture of 115mm. The output aperture of the imaging lens 4 is the same as that of the magnifying lens 42, meaning the emitted light from the laser source 1 exits through the output surface of the magnifying lens 42. Furthermore, the magnifying lens 42 has a relatively small aperture, making it suitable for small to medium-sized beam lamps. The advantage of this embodiment is that it ensures that the imaging lens 4 allows sufficient light to pass through, enabling the emitted light to form a bright beam.

[0033] As a new implementation method, combined with the appendix Figure 1 The optical path system also includes a color filter disk 2 located between the laser light source 1 and the imaging object 3. The imaging object 3 includes, but is not limited to, a fixed pattern disk or a cutting disk with multiple patterned pieces. The imaging object 3, the color filter disk 2, and the laser light source 1 are relatively close, which is beneficial for the light emitted from the laser light source 1 to form a clearer light spot. When the imaging object 3 is a patterned piece, the light emitted from the laser light source 1 can form a patterned light spot after passing through the patterned piece. When the imaging object 3 is a cutting disk, the light emitted from the laser light source 1 can form a regular polygonal light spot after passing through the patterned piece. When the type of imaging object 3 is different, the pattern and shape of the light spot formed by the light emitted from the laser light source 1 will change accordingly. The beneficial effect of this embodiment is that the color filter disk 2 and the imaging object 3 can be used to enrich the types of light spots formed by the light emitted from the laser light source, thereby enhancing the stage performance of the beam light.

[0034] As attached Figure 1 To be continued Figure 3 As shown, the working principle of this invention is as follows: The light emitted from the laser source 1 first passes through the color filter disk 2, which can change the color of the beam. Then, the light passes through the imaging object 3, forming a light spot of a specific shape or pattern. The light then enters the first lens group 41, where the first lens 411 effectively corrects aberrations, and the second lens 412 is responsible for converging the light. Together, they reduce the exit angle and form a narrower beam. Finally, the beam is expanded by the magnifying lens 42, further adjusting the exit angle and expanding the illumination range, ultimately presenting a clear, bright, and sharp light spot on the imaging surface.

Claims

1. An optical path system for a laser beam lamp, comprising a laser source, an imaging object, and an imaging lens arranged in sequence, wherein the imaging lens comprises: The first lens group includes a first lens with negative optical power and a second lens with positive optical power arranged in sequence. The first lens and the second lens are dry-cemented together, and the second lens is a spherical biconvex lens. A magnifying lens is coaxial with the first lens group and fixedly installed in the light-emitting direction of the first lens group; Its features include a first lens being an aspherical biconcave lens and a magnifying lens being a spherical biconvex lens; the total optical length of the imaging lens is TTL < 150 mm.

2. The optical path system for a laser beam lamp according to claim 1, characterized in that, The incident surface of the first lens is an even-order aspherical surface, and the radius of curvature of the cemented surface of the first and second lenses is -284 mm; the radius of curvature of the emitting surface of the second lens is 51 mm, the radius of curvature of the incident surface of the magnifying lens is -415 mm, and the radius of curvature of the emitting surface of the magnifying lens is 138 mm.

3. The optical path system for a laser beam lamp according to claim 1, characterized in that, The thickness of the first lens is 2mm, the thickness of the second lens is 30mm, and the thickness of the magnifying lens is 20mm.

4. The optical path system for a laser beam lamp according to claim 1, characterized in that, The total optical length of the imaging lens is 149mm.

5. The optical path system for a laser beam lamp according to claim 1, characterized in that, The light-emitting angle of the imaging lens is 1.3°.

6. The optical path system for a laser beam lamp according to claim 1, characterized in that, The first mirror group also includes a stepped pressure ring and a pressure ring, with the pressure ring sleeved and installed on the light-emitting end of the stepped pressure ring.

7. The optical path system for a laser beam lamp according to claim 6, characterized in that, The first lens and the second lens are installed inside the stepped pressure ring, and the aperture of the first lens is smaller than that of the second lens.

8. The optical path system for a laser beam lamp according to claim 1, characterized in that, F / #=1.18。 9. The optical path system for a laser beam lamp according to claim 1, characterized in that, The light-emitting aperture of the imaging lens is 115mm.

10. The optical path system for a laser beam lamp according to claim 1, characterized in that, It also includes a color plate disk located between the laser light source and the imaging object, the imaging object including but not limited to a fixed pattern disk or a cutting disk with multiple pattern pieces.

Images