A projection lamp system for oblique projection

Abstract

The present invention provides a projection lamp system for oblique projection, which includes a light source. On one side of the light-emitting surface of the light source, a collimating lens, a projection source, and a projection lens group are sequentially provided. A projection pattern is provided in the projection source. The two ends of the projection pattern are respectively a far projection point and a near projection point. The center of the projection pattern is collinear with the optical axis of the projection lens group. The distance between the optical axis of the light source and the far projection point is d, and the distance between the optical axis of the light source and the near projection point is D, where d < D. The present invention reasonably distributes the light energy distribution in the projection lamp system, reduces the incident angle of the light entering the far projection point, thereby effectively increasing the light energy entering the far projection point. During oblique projection, the light spot brightness in the place far from the projection lamp system is high enough and is basically equal to that in the place close to the projection lamp system. The entire light spot formed by the projection lamp system is clear, bright, and has uniform brightness everywhere.

Description

Technical Field

[0001] The invention relates to a projection lamp system, and in particular discloses a projection lamp system for inclined projection. Background Art

[0002] Projection technology is widely used in image display, welcome lighting, stage lighting and other fields. The traditional projection lamp system mainly includes projection sources such as LED, collimating lens, film and projection unit lens group. The imaging optical path of the traditional projection lamp system is as follows: Figure 1 As shown, the light irradiated by the light source passes through the projection source to form a shaped light and then passes through the lens group to realize the functions of projection and lighting.

[0003] Projection lamps can also be used outside the car body. When the projection lamp is set on the side of the car body, it can be used as a welcome or logo light. Some projection lamps are set on the front and back of the car body as warning reminders. When the projection lamp is tilted on the ground for projection, there will be a problem of uneven brightness of the projection spot, and the brightness of the spot far away from the projection lamp is insufficient. Summary of the invention

[0004] Based on this, it is necessary to provide a projection lamp system for tilted projection to address the problems of the prior art, which can form a clear and bright projection light spot during tilted projection.

[0005] In order to solve the problems in the prior art, the present invention discloses a projection lamp system for oblique projection, comprising a light source, a collimating lens, a projection source and a projection lens group are sequentially arranged on one side of a light emitting surface of the light source, a projection pattern is arranged in the projection source, two ends of the projection pattern are respectively a far projection point and a near projection point, the center of the projection pattern is collinear with the optical axis of the projection lens group, the distance between the optical axis of the light source and the far projection point is d, the distance between the optical axis of the light source and the near projection point is D, d <D。

[0006] Furthermore, at least one plane of the collimating lens is a non-rotationally symmetric plane.

[0007] Furthermore, the incident angle projected to the far projection point through the collimating lens is α, and α<10°.

[0008] Furthermore, the projection source is a film.

[0009] Furthermore, the projection lens group includes a first convex lens, a concave lens, and a second convex lens which are arranged in sequence, and the first convex lens is located on a side of the concave lens close to the projection source.

[0010] Furthermore, the optical axes of the first convex lens, the concave lens and the second convex lens are collinear.

[0011] The beneficial effects of the present invention are as follows: the present invention discloses a projection lamp system for oblique projection, which reasonably distributes the light energy distribution in the projection lamp system, reduces the incident angle of light entering a far projection point, thereby effectively increasing the light energy entering the far projection point. During oblique projection, the brightness of the light spot far away from the projection lamp system is high enough and is basically equal to the light spot close to the projection lamp system. The entire light spot formed by the projection lamp system is clear and bright, and the brightness is uniform everywhere. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 Schematic diagram of the imaging light path of a traditional projection lamp system.

[0013] Figure 2 It is a structural schematic diagram of the present invention.

[0014] Figure 3 Schematic diagram of energy collection of the present invention.

[0015] Figure 4 Schematic diagram of the imaging optical path of the present invention.

[0016] Figure 5 It is a structural diagram of oblique projection.

[0017] Figure 6 This is the illumination distribution diagram of the projection spot of the traditional projection lamp system.

[0018] Figure 7 This is the illumination distribution diagram of the projection spot of the present invention.

[0019] The reference numerals are: light source 10 , collimating lens 20 , projection source 30 , projection pattern 31 , far projection point 311 , near projection point 312 , projection lens group 40 , first convex lens 41 , concave lens 42 , second convex lens 43 . DETAILED DESCRIPTION

[0020] In order to further understand the features, technical means, specific objectives and functions of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0021] refer to Figures 1 to 7 .

[0022] The embodiment of the present invention discloses a projection lamp system for oblique projection, such as Figure 2As shown in the figure, it includes a light source 10. On one side of the light-emitting surface of the light source 10, a collimating lens 20, a projection source 30, and a projection lens group 40 are sequentially provided. A projection pattern 31 is provided in the projection source 30. The two ends of the projection pattern 31 are respectively a far projection point 311 and a near projection point 312. The projection light spot formed by the far projection point 311 is located at one end far from the projection lamp system, and the projection light spot passing through the near projection point 312 is located at one end close to the projection lamp system. The center of the projection pattern 31 is collinear with the optical axis of the projection lens group 40, and the center of the projection pattern 31 is located at the center of the connection line between the far projection point 311 and the near projection point 312. The connection line between the two vertexes of the collimating lens 20 is not coaxial with the projection lens group 40. The distance between the optical axis of the light source 10 and the far projection point 311 is d, and the distance between the optical axis of the light source 10 and the near projection point 312 is D, where d < D, that is, the optical axis of the light source 10 is arranged close to the far projection point 311. The incident angle of the light from the collimating lens 20 to the far projection point 311 is α, and the incident angle of the light from the collimating lens 20 to the near projection point 312 is β, where α > β. Once the incident angle is greater than the aperture angle, the light in this part cannot enter the imaging system, that is, it cannot pass through the projection source 30. Therefore, more energy enters the far projection point 311 and less energy enters the near projection point 312, that is, the light intensity at the near projection point 312 is smaller and the light intensity at the far projection point 311 is larger, ensuring that the illuminance of the projection light spot at the end far from the projection lamp system is large enough. The schematic diagram of energy collection is as shown in Figure 3 As shown in the figure, the schematic diagram of the imaging optical path is as shown in Figure 4 As shown.

[0023] As shown in Figure 5 As shown in the figure, when tilting the projection, the tilting angle is θ, the height of the projection lamp system is h, the illuminance is E, and the light intensity is I. The light intensity I satisfies the following formula: When the height h is constant and the illuminance E at each projection location needs to be equal, the light intensity I is inversely proportional to the tilting angle θ. The larger the tilting angle θ, that is, the farther the projection distance, the greater the required light intensity I. Arranging the optical axis of the light source 10 close to the far projection point 311 can effectively improve the light energy at the far projection point 311 and make the illuminance distribution of the projection light spots at each final projection position uniform.

[0024] When the tilting angle θ of the projection lamp system is 45° and the height h is 0.8 m, the illuminance distribution diagram of the traditional projection lamp is as shown in Figure 6 As shown in the figure, the illuminance distribution diagram of the projection lamp system of the present invention is as shown in Figure 7 As shown in the figure. It can be seen that the illuminance distribution of the projection lamp system of the present invention is uniform, and there will be no defect of insufficient projection brightness in the distance.

[0025] The present invention reasonably distributes the light energy distribution in the projection lamp system, reduces the incident angle of the light entering the far projection point, thereby effectively improving the light energy entering the far projection point. During oblique projection, the brightness of the light spot far away from the projection lamp system is high enough and is basically equal to the light spot near the projection lamp system. The entire light spot formed by the projection lamp system is clear and bright, and the brightness is uniform everywhere.

[0026] In this embodiment, at least one plane of the collimating lens 20 is a non-rotationally symmetric surface. The non-rotationally symmetric surface can cooperate with the light source 10 deviating from the projection lens group 40 to achieve a high-efficiency focusing effect, so that most of the light can pass through the projection pattern 31 in the projection source 30. The non-rotationally symmetric surface of the collimating lens 20 can be expressed by a multi-order xy polynomial: Where z is the height of the surface, c is the vertex curvature, k is the cone coefficient, C j is the coefficient of the subsequent sub-item. When the first-order differential of z is 0, there is only one solution, which is used to ensure that there is only one local maximum value and the surface shape is smooth.

[0027] In this embodiment, the incident angle of the light projected to the far projection point 311 by the collimating lens 20 is α, and α<10°.

[0028] In this embodiment, the projection source 30 is a film, the projection pattern 31 on the film is a light-transmitting pattern, and the angle of the collimated chief light reaching each field of view on the projection pattern 31 is β, β≈0°.

[0029] In this embodiment, the projection lens group 40 includes a first convex lens 41 , a concave lens 42 , and a second convex lens 43 which are arranged in sequence. The first convex lens 41 is located on a side of the concave lens 42 close to the projection source 30 .

[0030] Based on the above embodiment, the optical axes of the first convex lens 41 , the concave lens 42 and the second convex lens 43 are collinear.

[0031] The above-mentioned embodiments only express several implementation methods of the present invention, and the description thereof is relatively specific and detailed, but it cannot be understood as limiting the scope of the patent of the present invention. It should be pointed out that, for ordinary technicians in this field, several variations and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A projection lamp system for oblique projection, characterized in that: The invention comprises a light source (10), wherein a collimating lens (20), a projection source (30) and a projection lens group (40) are sequentially arranged on one side of a light emitting surface of the light source (10), wherein a projection pattern (31) is arranged in the projection source (30), wherein two ends of the projection pattern (31) are respectively a far projection point (311) and a near projection point (312), wherein the center of the projection pattern (31) is collinear with an optical axis of the projection lens group (40), wherein the distance between the optical axis of the light source (10) and the far projection point (311) is d, and the distance between the optical axis of the light source (10) and the near projection point (312) is D, and wherein d <D; The collimating lens (20) has at least one plane that is a non-rotationally symmetrical plane; The incident angle projected onto the far projection point (311) through the collimating lens (20) is α, α<10°; The projection lens group (40) comprises a first convex lens (41), a concave lens (42) and a second convex lens (43) which are arranged in sequence, and the first convex lens (41) is located on a side of the concave lens (42) close to the projection source (30).

2. A projection lamp system for oblique projection according to claim 1, characterized in that: The projection source (30) is a film.

3. The projection lamp system for oblique projection according to claim 1, characterized in that: The optical axes of the first convex lens (41), the concave lens (42) and the second convex lens (43) are collinear.

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