Projection lens module having micro lens array, and projection lamp having same
The projection lens module with dual micro-lens arrays and a light blocker or light-blocking pattern addresses unwanted light emission and improves image clarity by blocking stray light, enhancing MTF for clearer images.
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- OPTRONTEC INC
- Filing Date
- 2025-11-27
- Publication Date
- 2026-06-11
Smart Images
Figure KR2025019978_11062026_PF_FP_ABST
Abstract
Description
Projection lens module having a micro-lens array and a projection lamp having the same
[0001] The present invention relates to a projection lens module and a projection lamp, and in particular, to a projection lens module having a micro-lens array and a projection lamp having the same.
[0002] Projection lamps that emit light using imaging lenses are used for various purposes, such as vehicle headlights and signal lamps. Meanwhile, projection lamps employing micro-lens arrays are generally used to reduce the size of the lamp.
[0003] However, conventional projection lamps are prone to problems where light emitted through the areas between micro-lenses or their edges fails to form an image at the desired location. Consequently, unwanted light is emitted from the lamp, degrading its performance. For example, in the case of headlights, the irradiation of unwanted light can cause accidents, while in the case of signal lamps, it makes it difficult to achieve a clear image.
[0004] The problem that the present invention aims to solve is to provide a projection lens module capable of blocking the emission of unnecessary light and a projection lamp having the same.
[0005] Another problem that the present invention aims to solve is to provide a projection lens module that improves the clarity of a projected image and a projection lamp having the same.
[0006] A projection lens module according to one embodiment of the present invention comprises a light-emitting lens and an imaging lens disposed above the light-emitting lens, wherein the light-emitting lens has a first micro-lens array and the imaging lens has a second micro-lens array and the second micro-lens array is composed of features applied to both sides of the imaging lens.
[0007] The second microlens array can be arranged corresponding to the first microlens array.
[0008] In one embodiment, the features applied to both sides of the imaging lens include first features disposed on the light-emitting surface side of the imaging lens and second features disposed on the light-incoming surface side of the imaging lens, and the first features may have a convex aspherical shape.
[0009] The second microlens array above can be formed from a single material.
[0010] Meanwhile, the second features mentioned above may have a concave aspherical shape.
[0011] In one embodiment, the projection lens module may further include a light blocker disposed between the light-displaying lens and the imaging lens to block a portion of the light passing through the light-displaying lens and incident on the imaging lens, and the light blocker may block light incident from the light-displaying lens to the boundary region of the micro-lenses of the second micro-lens array.
[0012] In one embodiment, the light blocker may have a mesh shape.
[0013] In one embodiment, the projection lens module may further include an image pattern disposed between the illumination lens and the imaging lens.
[0014] The above image pattern can be placed on the light emission side of the light-emitting lens.
[0015] The projection lens module may further include a transparent substrate disposed between the light-dissipating lens and the imaging lens, and the image pattern may be disposed on one surface of the transparent substrate.
[0016] In one embodiment, the projection lens module may further include a light-blocking pattern disposed on the other side of the transparent substrate, and the light-blocking pattern may block light incident from the light-diffusing lens to the boundary region of the micro-lenses of the second micro-lens array.
[0017] A projection lamp according to one embodiment of the present invention includes a light source and a projection lens module as described above.
[0018] According to embodiments of the present invention, a projection lens module and a projection lamp having the same can be provided, which can block the emission of unnecessary light and further improve the clarity of a projected image.
[0019] FIG. 1 is a schematic cross-sectional view illustrating a projection lamp according to one embodiment of the present invention.
[0020] FIG. 2 is a schematic exploded cross-sectional view for explaining a projection lens module according to one embodiment of the present invention.
[0021] FIG. 3 is a schematic exploded cross-sectional view illustrating a projection lens module according to another embodiment of the present invention.
[0022] Figure 4 is a graph illustrating the diffraction MTF according to the prior art.
[0023] FIG. 5 is a schematic diagram illustrating a projected image of a signal lamp according to the prior art.
[0024] FIG. 6 is a graph illustrating a diffraction MTF according to one embodiment of the present invention.
[0025] FIG. 7 is a graph illustrating a diffraction MTF according to another embodiment of the present invention.
[0026] Hereinafter, embodiments of the present invention will be described in detail with reference to the attached drawings. The embodiments described below are provided as examples to ensure that the concept of the present invention is sufficiently conveyed to those skilled in the art. Accordingly, the present invention is not limited to the embodiments described below and may be embodied in other forms. Furthermore, in the drawings, the width, length, thickness, etc., of components may be exaggerated for convenience. Throughout the specification, the same reference numerals indicate the same components.
[0027] FIG. 1 is a schematic cross-sectional view for explaining a projection lamp (100) according to one embodiment of the present invention, and FIG. 2 is a schematic exploded cross-sectional view for explaining a projection lens module (30) according to one embodiment of the present invention.
[0028] Referring to FIG. 1, the projection lamp (100) may include a light source (10), a collimator (20), and a projection lens module (30). In this embodiment, the projection lamp (100) is described as a signal lamp, but it is not necessarily limited thereto and may be applied to other types of vehicle lamps, such as head lamps or fog lamps.
[0029] The light source (10) generates light that is incident on the projection lens module (30). The light source (10) may include, for example, a light-emitting diode. Although a single light source (10) is shown in this embodiment, a larger number of light sources (10) may be arranged and used.
[0030] The collimator (20) is positioned between the light source (10) and the projection lens module (30) to collimate light incident from the light source (10) and emit it to the projection lens module (30). The collimator (20) causes parallel light to be incident on the projection lens module (30). If the light source (10) emits parallel light such as a laser, the collimator (20) may be omitted.
[0031] The projection lens module (30) emits light incident from the light source (10) to the outside. In the case of a headlamp, the projection lens module (30) can illuminate the front of the vehicle by emitting light in the required direction. In the case of a signal lamp, the projection lens module (30) can create a signal image using light incident from the light source (10).
[0032] Referring to FIG. 2, in one embodiment, the projection lens module (30) may include a light-diffusing lens (31), an image pattern (33), an imaging lens (35), and a light blocker (37).
[0033] The light-emitting lens (31) may include a first micro-lens array. The first micro-lens array may be composed of micro-lenses (31a) having a convex shape toward the light source (10). The first micro-lens array may be manufactured by injection molding a single material or by using imprint technology on a single material.
[0034] In one embodiment, the image pattern (33) may be placed on the light-emitting surface of the light-emitting lens (31). The image pattern (33) corresponds to an image to be implemented in the signal lamp. The image pattern (33) may be formed of a light-blocking material.
[0035] The imaging lens (35) includes a second micro-lens array. The second micro-lens array is positioned corresponding to the first micro-lens array. The second micro-lens array may be composed of first and second features (35a, 35b) applied to both sides of the imaging lens (35). A pair of first and second features (35a, 35b) may constitute the second micro-lens.
[0036] A second micro-lens array having first and second features (35a, 35b) can be manufactured, for example, by injection molding using a single material. By manufacturing the second micro-lens array with a single material, light scattering caused by differences in refractive index within can be prevented, thereby preventing the generation of unwanted light due to internal light scattering.
[0037] The first features (35a) are positioned on the light-emitting side of the imaging lens (35), and the second features (35b) are positioned on the light-incoming side of the imaging lens (35). As shown in FIG. 2, the first features (35a) may have a convex aspherical shape, and the second features (35b) may have a concave aspherical shape. By using the first features (35a) and the second features (35b) formed on both sides of the imaging lens (35), unnecessary light that cannot be used to create an image can be reduced.
[0038] In this embodiment, the second features (35b) are illustrated and described as having a concave shape, but the present invention is not limited thereto. For example, the second features (35b) may have an aspherical shape that is convex toward the light source (10).
[0039] By forming first and second features (35a, 35b) on both sides of the imaging lens (35), the generation of unnecessary light among the light passing through the imaging lens (35) can be reduced, and this will be explained in detail later with reference to FIGS. 4 to 7.
[0040] A light blocker (37) may be positioned between the light-emitting lens (31) and the imaging lens (25). In one embodiment, the light blocker (37) may have a mesh shape and blocks a portion of the light incident on the imaging lens (35) through the light-emitting lens (31). In particular, the light blocker (37) may block light incident from the light-emitting lens (31) to the boundary region of the micro-lenses of the second micro-lens array.
[0041] Generally, due to aberrations or difficulties in lens manufacturing, light incident on the edges of micro-lenses is likely to become unwanted light that cannot be refracted to a focal point. Therefore, unwanted light can be removed by blocking light incident on the edges of micro-lenses using a light blocker (37).
[0042] The light-emitting lens (31), the imaging lens (35), and the light blocker (37) can be attached to each other and combined integrally on the outer side of the micro-lens array area.
[0043] In this embodiment, unnecessary light can be reduced by using the first and second features (35a, 35b) applied to both sides of the imaging lens (35), and furthermore, unnecessary light can be further removed by adding a light blocker (37).
[0044] In the present embodiment, a projection lens module (30) including a light blocker (37) and an imaging lens (35) having first and second features (35a, 35b) applied to both sides is described, but the present invention is not limited to including both the imaging lens (35) and the light blocker (37). For example, the light blocker (37) may be omitted in the projection lens module (30), and instead of including the light blocker (37), the second micro-lens array may be composed of features formed on one side of the imaging lens (35), such as the first features (35a) or the second features (35b).
[0045] FIG. 3 is a schematic exploded cross-sectional view illustrating a projection lens module (30a) according to another embodiment of the present invention.
[0046] Referring to FIG. 3, the projection lens module (30a) according to the present embodiment is generally similar to the projection lens module (30) described with reference to FIG. 2, but differs in that it includes a transparent substrate (39) having a light blocking pattern (37a) instead of a light blocker (37).
[0047] The transparent substrate (39) may be, for example, a glass substrate. The light-emitting lens (31) and the imaging lens (35) may be attached to the transparent substrate (39). In this embodiment, the image pattern (33a) may be placed on the lower surface of the transparent substrate (39) as shown in FIG. 3. However, the present invention is not limited thereto, and the image pattern (33a) may be placed on the light-emitting lens (31) as shown in FIG. 2.
[0048] The light blocking pattern (37a) can be formed in a mesh shape similar to the light blocker (37) and blocks a portion of the light incident on the imaging lens (35) through the light-displaying lens (31). In particular, the light blocking pattern (37a) can block light incident from the light-displaying lens (31) to the boundary region of the micro-lenses of the second micro-lens array.
[0049] According to the present embodiment, unnecessary light can be removed by adopting a transparent substrate (39) having a light-blocking pattern (37a) formed thereon.
[0050] In this embodiment, the imaging lens (35) may have a micro-lens array composed of at least one of the first features and the second features.
[0051] FIG. 4 is a graph for explaining diffraction MTF according to the prior art, and FIG. 5 is a schematic diagram for explaining the projected image of a signal lamp according to the prior art.
[0052] Conventional imaging lenses are composed of features formed on the cross-section, and accordingly, the diffraction MTF (Modulation Transfer Function) tends to decrease as the spatial frequency increases, and a significant amount exhibits an MTF less than 0.4 at 40 cycles / mm. Therefore, a significant amount of light emitted through conventional imaging lenses becomes unnecessary light.
[0053] Referring to FIG. 5, light passing through the imaging lens forms an image (51) corresponding to an image pattern (33) in a required area such as a ground, but as shown in FIG. 4, an area (53) with poor contrast of the image (51) is formed by light with low MTF, resulting in reduced image clarity, and furthermore, an unwanted image (55) may be formed.
[0054] FIG. 6 is a graph for explaining diffraction MTF according to one embodiment of the present invention, and FIG. 7 is a graph for explaining rotational MTF according to another embodiment of the present invention. The embodiment of FIG. 6 is an example of an imaging lens (35) in which both the first features (35a) and the second features (35b) are formed in a convex aspherical shape, and the embodiment of FIG. 7 shows an example of an imaging lens (35) in which the first feature is formed in a convex aspherical shape and the second features (35b) are formed in a concave aspherical shape.
[0055] Referring to FIGS. 6 and 7, it can be seen that by adopting the first features (35a) and the second features (35b), the MTF of most light at 40 cycles / mm can be made greater than 0.4, and thus, unnecessary light can be significantly removed. In particular, when comparing the position at 40 cycles / mm, it can be seen that when the second features (35b) are formed in a concave aspherical shape (Fig. 7), the MTF values are all greater than 0.5, and that unnecessary light is further reduced compared to when the second features (35b) are formed in a concave shape (Fig. 6).
[0056] Although various embodiments have been described above, the present invention is not limited to these embodiments and can be modified in various ways without departing from the scope of the invention.
Claims
1. Light-emitting lens; and It includes an imaging lens positioned above the light-emitting lens, and The above-mentioned light-diffusing lens has a first micro-lens array, and The above imaging lens has a second microlens array, and The second microlens array is a projection lens module composed of features applied to both sides of the imaging lens.
2. In Claim 1, The second micro-lens array is a projection lens module positioned in correspondence with the first micro-lens array.
3. In Claim 1, The features applied to both sides of the imaging lens include first features disposed on the light-emitting surface side of the imaging lens and second features disposed on the light-receiving surface side of the imaging lens, and The first features above are projection lens modules having a convex aspherical shape.
4. In Claim 3, The above second features are projection lens modules having a concave aspherical shape.
5. In Claim 1, The second micro-lens array above is a projection lens module formed from a single material.
6. In Claim 1, It further includes a light blocker disposed between the light-displaying lens and the imaging lens to block a portion of the light passing through the light-displaying lens and incident on the imaging lens, The light blocker is a projection lens module that blocks light incident from the light-diffusing lens to the boundary region of the micro-lenses of the second micro-lens array.
7. In Claim 6, The above light blocker is a projection lens module having a mesh shape.
8. In Claim 1, A projection lens module further comprising an image pattern disposed between the light-dissipating lens and the imaging lens.
9. In Claim 8, The above image pattern is a projection lens module positioned on the light emission side of the above light-emitting lens.
10. In claim 8, It further includes a transparent substrate disposed between the light-diffusing lens and the imaging lens, and The above image pattern is a projection lens module disposed on one side of the transparent substrate.
11. In Claim 10, The light-blocking pattern further comprises a light-blocking pattern disposed on the other side of the transparent substrate, The light blocking pattern above is a projection lens module that blocks light incident from the light-dampening lens to the boundary region of the micro-lenses of the second micro-lens array.
12. Light source; and A projection lamp comprising a projection lens module as described in any one of claims 1 to 11.