Film projection lamp capable of electrically focusing and electric focusing method

Abstract

The invention discloses an electric focusing film projection lamp and an electric focusing method, and belongs to the technical field of vehicle lamp control. The electric focusing method comprises the following steps: acquiring an initial projection image through a vehicle-mounted camera; performing image preprocessing on the initial projection image acquired by the vehicle-mounted camera; performing contrast calculation on the initial projection image after image preprocessing; and judging whether the calculated contrast reaches a preset contrast threshold value or not, if so, ending the process, and if not, performing focusing through rotation of the driving motor until the contrast of the projected image reaches the preset contrast threshold value. The film projection lamp can adapt to different loading heights, and the definition of projection patterns in different scenes is improved.

Description

TECHNICAL FIELD

[0001] The application relates to an electrically adjustable focus film projection lamp and an electrically adjustable focus method, and belongs to the technical field of vehicle lamp control. BACKGROUND

[0002] At present, with the increasing requirement of people on the configuration of automobiles, as important equipment for improving individualization and sense of ceremony, projection lamps are applied to more and more vehicles. Users can project exclusive designed brand logos and individual patterns to the ground to strengthen the recognition of vehicles. Among them, the film projection lamp is dominant in the vehicle projection market due to low cost and high stability, and the main principle thereof is to realize a pattern by using a film to shield light, and the structure thereof is generally composed of an LED, a collimating lens, a film and a projection lens, and the positions of the components are fixed and cannot be adjusted. However, due to assembly errors and manufacturing errors, the lens cannot always be kept at the designed position, thereby affecting the projection pattern effect.

[0003] In the prior art, the film projection lamp generally adopts a fixed focus design, which means that a specific projection distance is set when the lamp is shipped, and only at the specific projection distance can a clear preset pattern be formed. However, manufacturing errors or assembly errors may exist in the installation position of the lamp, which will result in that the film projection lamp cannot be kept at the specific projection distance from the ground. In addition, when facing various installation positions, such as a vehicle door step, an outside rearview mirror, a back door, a vehicle chassis and the like, the film projection lamp with a fixed focus cannot be flexibly adjusted after the vehicle is shipped, and it is difficult to guarantee the projection pattern effect. SUMMARY

[0004] The application aims to overcome the defects of the prior art and provide an electrically adjustable focus film projection lamp and an electrically adjustable focus method, which can adapt to different loading heights and improve the clarity of the projection pattern in different scenes.

[0005] To solve the above technical problems, the technical scheme of the application is as follows:

[0006] In one aspect, the application provides an electrically adjustable focus method of an electrically adjustable focus film projection lamp, which comprises the following steps:

[0007] Step S1: collecting an initial projection image by using a vehicle-mounted camera;

[0008] Step S2: performing image preprocessing on the initial projection image collected by the vehicle-mounted camera;

[0009] Step S3: performing contrast calculation on the initial projection image after the image preprocessing;

[0010] Step S4, judging whether the calculated contrast reaches a preset contrast threshold, if yes, the flow ends, if not, jumping to step S5;

[0011] Step S5, focusing by driving the motor to rotate until the contrast of the projection image reaches the preset contrast threshold.

[0012] Further, in the step S2, the initial projection image collected by the vehicle-mounted camera is pre-processed, specifically including the following steps:

[0013] Step S21, color space conversion is performed on the initial projection image collected by the vehicle-mounted camera;

[0014] Step S22, Gaussian filter noise reduction processing is performed on the initial projection image after color space conversion;

[0015] Step S23, the region of interest is extracted from the initial projection image after Gaussian filter noise reduction processing.

[0016] Further, in the step S21, color space conversion is performed on the initial projection image collected by the vehicle-mounted camera, specifically including the following steps:

[0017] The RGB color image of the initial projection image is converted into a gray image.

[0018] Further, the calculation formula of the contrast is as follows:

[0019]

[0020] Wherein, C is the contrast of the projection image after image preprocessing;

[0021] I max is the maximum value of all pixel gray values of the projection image after image preprocessing;

[0022] I min is the minimum value of all pixel gray values of the projection image after image preprocessing.

[0023] Further, in the step S5, focusing is performed by driving the motor to rotate until the contrast of the projection image reaches the preset contrast threshold, specifically including the following steps:

[0024] Step S51, driving the motor to rotate in a preset direction by a preset small step value;

[0025] Step S52, collecting a second projection image after motor rotation by the vehicle-mounted camera;

[0026] Step S53, pre-processing the second projection image collected by the vehicle-mounted camera;

[0027] Step S54, contrast calculation is performed on the second projection image after image preprocessing;

[0028] Step S55, the contrast of the initial projection image and the second projection image is compared, and a corresponding focusing strategy is adopted according to the comparison result.

[0029] Further, in the step S55, the contrast of the initial projection image and the second projection image is compared, and a corresponding focusing strategy is adopted according to the comparison result, specifically including the following steps:

[0030] If the contrast of the initial projection image is greater than the contrast of the second projection image, the motor is driven to rotate in the opposite direction of the preset direction by a preset small step value until the contrast of the projection image reaches a preset contrast threshold;

[0031] If the contrast of the initial projection image is less than the contrast of the second projection image, the motor is driven to rotate in the preset direction by a preset small step value until the contrast of the projection image reaches a preset contrast threshold.

[0032] Another aspect of the present application provides a film projection lamp, which comprises a limiting ornament ring, a lens, a gear lens barrel, a support, a film sheet, a light source assembly and a focusing driving assembly;

[0033] The support is provided with a light outlet, the film sheet covers the light outlet, and the film sheet is provided with a lens barrel connecting ring at the outer periphery;

[0034] One end of the gear lens barrel is located in the limiting ornament ring, the lens is fixed at one end of the gear lens barrel, and the other end of the gear lens barrel is threadedly connected with the lens barrel connecting ring;

[0035] The focusing driving assembly is arranged in the support, the focusing driving assembly is used for driving the gear lens barrel to rotate, and the gear lens barrel is used for driving the lens to linearly displace in the limiting ornament ring along the optical axis direction;

[0036] The light source assembly is arranged in the support, the light source assembly is used for providing a light source, and the light emitted by the light source assembly is emitted from the lens after sequentially passing through the light outlet and the film sheet.

[0037] Further, the support is provided with a first groove, and the first groove is used for mounting the film sheet;

[0038] The support is provided with a second groove, the second groove is located in the first groove, and the light outlet is located in the second groove;

[0039] The second groove is further provided with positioning columns, and the two positioning columns are located on the two sides of the light outlet, respectively.

[0040] Further, the focusing driving assembly comprises a motor and a motor gear, and the top of the support is provided with a mounting groove;

[0041] The motor is arranged in the mounting groove, and the motor gear is connected with the motor and used for rotating under the driving of the motor and driving the gear lens barrel to rotate.

[0042] Further, the light source assembly comprises a light source plate and a light guide, and the light source plate is provided with an LED lamp;

[0043] The light source plate is connected with the support, the light guide penetrates through the light outlet, one end of the light guide is arranged opposite to the LED lamp, the other end of the light guide is arranged in the second groove, and the other end of the light guide is inserted with the positioning column, and the light emitted by the LED lamp is sequentially emitted from the lens after passing through the light guide, the light outlet and the film.

[0044] By adopting the above technical scheme, the present application has the following beneficial effects:

[0045] When the motor rotates, the motor gear drives the gear lens barrel to rotate together, the gear lens barrel drives the lens to linearly displace in the limiting ring along the optical axis direction, and the electric focusing function of the film projection lamp is realized. The projection image is collected by the vehicle-mounted camera and sent to the vehicle lamp controller for identification and processing, and then the vehicle lamp controller controls the motor to rotate until the projection image reaches the preset contrast threshold, and the automatic focusing function of the film projection lamp is realized. The film projection lamp of the present application can adapt to more extensive installation position requirements, improve the clarity of the projection pattern in different scenes, reduce the requirement for installation precision, and has strong installation adaptability. BRIEF DESCRIPTION OF DRAWINGS

[0046] Figure 1 The electric focusing method flow chart of the electrically focusable film projection lamp of the present application;

[0047] Figure 2 The structural explosion diagram of the film projection lamp of the present application;

[0048] Figure 3 The structural diagram of the support of the present application;

[0049] Figure 4 The structural diagram of the light guide of the present application. DETAILED DESCRIPTION

[0050] In order to make the content of the present application more easily understood, the present application will be further described in detail below according to specific embodiments and in combination with the drawings.

[0051] Embodiment one

[0052] As Figure 1As shown, the embodiment provides an electric focusing method of a film projection lamp, which can automatically identify a projection pattern and dynamically adjust a focal length in real time, can adapt the film projection lamp to different loading heights, can adapt to more extensive installation position requirements, and improves the clarity of the projection pattern in different scenes. It comprises the following steps:

[0053] Step S1, collecting an initial projection image through a vehicle-mounted camera. The initial projection image collected by the vehicle-mounted camera is an RGB color image. The initial projection image is used to provide a basis for subsequent electric focusing.

[0054] Step S2, performing image preprocessing on the initial projection image collected by the vehicle-mounted camera through a vehicle light controller. Specifically, it comprises the following steps:

[0055] Step S21, performing color space conversion on the initial projection image collected by the vehicle-mounted camera, i.e. converting the RGB color image of the initial projection image into a grayscale image, so as to facilitate subsequent contrast calculation. Different color spaces can reveal different features of the image and are suitable for different analysis and processing tasks.

[0056] Step S22, performing Gaussian filter denoising processing on the initial projection image after color space conversion. The Gaussian filter denoising processing is used to process Gaussian noise, which can remove noise while minimizing the blurring degree of image details, thereby improving the precision and accuracy of subsequent image processing.

[0057] Step S23, performing region of interest extraction on the initial projection image after Gaussian filter denoising processing. The region of interest extraction refers to the extraction of a specific region from the image through a rectangle, a circle, etc. for targeted processing, which can improve the calculation efficiency and reduce the calculation amount.

[0058] Step S3, performing contrast calculation on the initial projection image after image preprocessing through the vehicle light controller. Contrast is a quantitative indicator of the difference between light and dark in an image. The difference between the brightest part and the darkest part of a clear image is very large. The greater the difference, the richer the image details, so the higher the contrast and the better the clarity. The contrast is calculated based on the extreme dynamic range, and the specific calculation formula is as follows:

[0059]

[0060] Wherein, C is the contrast of the projection image after image preprocessing;

[0061] I max is the maximum value of all pixel grayscale values of the projection image after image preprocessing;

[0062] I minThe minimum value of the gray scale values of all pixels of the image pre-processed projection image.

[0063] Step S4, judging whether the calculated contrast reaches the preset contrast threshold value, if yes, the flow ends, if not, jumping to step S5. The preset contrast threshold value in the embodiment is 0.3, which is obtained by calibration.

[0064] Step S5, focusing by driving the motor to rotate until the contrast of the projection image reaches the preset contrast threshold value, which can reduce the factory debugging time and improve the assembly efficiency. The specific method of focusing by driving the motor to rotate is the hill climbing algorithm, including the following steps:

[0065] Step S51, driving the motor to rotate by a preset small step value in a preset direction. The preset small step value is a fixed and small angle, and the preset small step value in the embodiment is 1.8°. The angle of the motor rotating each time is according to the preset small step value. In the embodiment, the vehicle lamp controller sends a short pulse sequence to the motor to control the motor to rotate once in the preset direction (for example, clockwise), and the rotation angle is 1.8°.

[0066] Step S52, collecting a second projection image after the motor rotates the small step value by the vehicle-mounted camera, and the second projection image is an RGB color image.

[0067] Step S53, image pre-processing the second projection image collected by the vehicle-mounted camera. The image pre-processing method of the second projection image is the same as that of the initial projection image.

[0068] Step S54, performing contrast calculation on the image pre-processed second projection image. The contrast calculation method of the second projection image is the same as that of the initial projection image.

[0069] Step S55, comparing the contrast of the initial projection image and the second projection image, and taking corresponding focusing strategy according to the comparison result. If the contrast of the initial projection image is greater than that of the second projection image, it means that the focusing direction is wrong, then the motor is driven to rotate by the preset small step value in the opposite direction of the preset direction, that is, the motor is driven to rotate counterclockwise each time by 1.8° until the contrast of the projection image reaches the preset contrast threshold value; if the contrast of the initial projection image is less than that of the second projection image, it means that the focusing direction is correct, then the motor is driven to rotate by the preset small step value in the preset direction, that is, the motor is still driven to rotate clockwise each time by 1.8° until the contrast of the projection image reaches the preset contrast threshold value.

[0070] Embodiment two

[0071] As Figure 2As shown, this embodiment provides a film projection lamp that uses the electric focusing method as described in Embodiment 1. It includes a limiting decorative ring 1, a lens 2, a gear lens barrel 3, a bracket 4, a film 5, a light source assembly 6, a focusing drive assembly 7, and a heat sink 8.

[0072] like Figure 2 As shown, the focusing drive assembly 7 in this embodiment is used to drive the geared lens barrel 3 to rotate. The focusing drive assembly 7 includes a motor 72 and a motor gear 71. The motor 72 is electrically connected to the vehicle light controller via a wiring harness. A mounting slot 46 is provided on the top of the bracket 4. The motor 72 is fixed in the mounting slot 46 by the motor bracket. The motor gear 71 is fixed to the motor 72 by an interference fit or by a spline connection. The vehicle light controller controls the motor 72 to drive the motor gear 71 to rotate, and then the motor gear 71 drives the geared lens barrel 3 to rotate, realizing the electric focusing function of the film projection.

[0073] like Figure 3 As shown, the bracket 4 in this embodiment has a light-emitting port 41, and the bracket 4 in this embodiment also has a first groove 42 and a second groove 43. The light-emitting port 41 is located in the second groove 43, and the second groove 43 is located in the first groove 42.

[0074] Specifically, the first groove 42 is used to install the film 5, which covers the light outlet 41. Circular grooves 421 are provided at the four corners of the first groove 42. The film 5 is placed in the first groove 42, and glue is applied to the four circular grooves 421 to fix it in place. The circular grooves 421 also provide installation space at the four corners of the film 5 to prevent it from being unable to be smoothly installed into the first groove 42. Specifically, the second groove 43 also contains positioning posts 44, with two positioning posts 44 located on either side of the light outlet 41.

[0075] like Figure 2 and 4 As shown, the light source assembly 6 in this embodiment includes a light source board 61 and a light guide 62. The light source board 61 is provided with an LED lamp 63 and a connector 64. The light guide 62 includes a light guide 621 and a fixing member 622. The light guide 621 and the fixing member 622 are connected. The fixing member 622 is provided with a through hole 6221.

[0076] Specifically, the light source board 61 is fixed on the bracket 4 by screws, the light guide 62 penetrates the light outlet 41, one end of the light guide 62 is arranged opposite to the LED lamp 63, the other end of the light guide 62 is arranged in the second groove 43, and the other end of the light guide 62 is also inserted with the positioning column 44 through the through hole 6221. The connector 64 is electrically connected with the vehicle lamp controller through a wire harness, and the connector 64 is also connected with the power supply of the whole vehicle through a wire harness. The vehicle lamp controller controls the LED lamp 63 to light, and the light emitted by the LED lamp 63 successively passes through the light guide 62, the light outlet 41 and the film 5 and then is emitted from the lens 2.

[0077] As shown in Figure 2 The radiator 8 of the embodiment is used for radiating heat for the light source board 61, the radiator 8 is connected with the light source board 61 by screws, and the radiator 8 is located on the side opposite to the light emitting direction of the light source board 61.

[0078] As shown in Figure 2 The film 5 of the embodiment is provided with a lens barrel connecting ring 45 on the outer periphery, and the lens barrel connecting ring 45 is connected with the bracket 4. The gear lens barrel 3 of the embodiment includes a lens barrel 31 and a focusing gear 32, and the outer wall of the lens barrel 31 is provided with a limiting piece 33. The limiting ornament ring 1 of the embodiment is fixed on the vehicle body panel, and the limiting ornament ring 1 is provided with a limiting groove 11. Specifically, one end of the lens barrel 31 is located in the limiting ornament ring 1, and the limiting piece 33 is located in the limiting groove 11. The lens 2 is fixed on one end of the lens barrel 31 by glue dispensing, and the other end of the lens barrel 31 is threadedly connected with the lens barrel connecting ring 45. The focusing gear 32 is engaged with the motor gear 71, and after the motor 72 is started, the motor 72 controls the motor gear 71 to rotate, the motor gear 71 drives the focusing gear 32 to rotate, and then the focusing gear 32 drives the lens 2 to linearly displace in the limiting ornament ring 1 along the optical axis direction, so that the electric focusing function of the film projection lamp is realized. When the lens 2 linearly displaces, the limiting piece 33 can only move in the range of the limiting groove 11, can constrain the moving range of the lens 2, and ensures that the focusing stroke is in a safe range.

[0079] Since the film projection lamp of the embodiment can realize automatic focusing, it can be adapted to a plurality of different installation positions, reduces the requirement for installation precision, and has strong installation adaptability. The typical installation positions of the film projection lamp of the embodiment include a trunk switch button position, a rear bumper area, an automobile chassis, a front bumper area and an interior of a rearview mirror.

[0080] The working principle of the application is as follows:

[0081] The initial projection image is collected by a vehicle-mounted camera; the initial projection image collected by the vehicle-mounted camera is preprocessed; the initial projection image after the image preprocessing is subjected to contrast calculation; whether the calculated contrast reaches a preset contrast threshold is judged, if yes, the process is ended, if not, the focusing is adjusted by rotating the driving motor until the contrast of the projection image reaches the preset contrast threshold.

[0082] When the motor rotates, the motor gear drives the gear lens barrel to rotate together, the gear lens barrel drives the lens to move linearly along the optical axis direction in the limiting decorative ring, the electric focusing function of the film projection lamp is realized. The projection image is collected by the vehicle-mounted camera and sent to the vehicle lamp controller for identification and processing, then the vehicle lamp controller controls the motor to rotate until the projection image reaches the preset contrast threshold, the automatic focusing function of the film projection lamp is realized. The film projection lamp of the application can adapt to more extensive installation position requirements, improves the clarity of the projection pattern in different scenes, reduces the requirement for installation precision, and has strong installation adaptability.

[0083] The above specific embodiments further illustrate the technical problems solved by the application, technical solutions and beneficial effects, and it should be understood that the above only describes specific embodiments of the application and is not intended to limit the application, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the application should be included in the protection scope of the application.

Claims

1. An electric focusing method of an electrically focusable film projection lamp, characterized by, It comprises the following steps: Step S1, collecting an initial projection image through a vehicle-mounted camera; Step S2, performing image preprocessing on the initial projection image collected by the vehicle-mounted camera; Step S3, performing contrast calculation on the initial projection image after image preprocessing; Step S4, judging whether the calculated contrast reaches a preset contrast threshold, if yes, the process ends, if not, jumping to step S5; Step S5, focusing by rotating the driving motor until the contrast of the projection image reaches the preset contrast threshold.

2. The electric focusing method of the electrically electrically focusing film projection lamp according to claim 1, characterized in that, In the step S2, the initial projection image collected by the vehicle-mounted camera is preprocessed, specifically comprising the following steps: Step S21, color space conversion is performed on the initial projection image collected by the vehicle-mounted camera; Step S22, Gaussian filter noise reduction processing is performed on the initial projection image after color space conversion; Step S23, the region of interest is extracted from the initial projection image after Gaussian filter noise reduction processing.

3. The electric focusing method of the electrically electrically focusing film projection lamp according to claim 2, characterized in that, In the step S21, the initial projection image collected by the vehicle-mounted camera is color space converted, specifically comprising the following steps: The RGB color image of the initial projection image is converted into a gray image.

4. The electric focusing method of the electrically electrically focusing film projection lamp according to claim 1, characterized in that, The formula for calculating the contrast is as follows: Wherein, C is the contrast of the projection image after image preprocessing; I max is the maximum value of the gray scale values of all pixels of the projection image after image pre-processing; I min is the minimum value of the gray scale values of all pixels of the projection image after image preprocessing.

5. The electric focusing method of the electrically electrically focusing film projection lamp according to claim 1, wherein, In the step S5, the driving motor is rotated for focusing until the contrast of the projection image reaches the preset contrast threshold, specifically comprising the following steps: Step S51, the driving motor is rotated by a preset small step value in a preset direction; Step S52, collecting a second projection image after motor rotation through the vehicle-mounted camera; Step S53, performing image preprocessing on the second projection image collected by the vehicle-mounted camera; Step S54, performing contrast calculation on the second projection image after image preprocessing; Step S55, comparing the contrast of the initial projection image and the second projection image, and adopting a corresponding focusing strategy according to the comparison result.

6. The electric focusing method of the electrically electrically focusing film projection lamp according to claim 5, characterized in that, In the step S55, the contrast of the initial projection image and the second projection image is compared, and a corresponding focusing strategy is adopted according to the comparison result, specifically comprising the following steps: If the contrast of the initial projection image is greater than that of the second projection image, the driving motor is rotated by a preset small step value in the opposite direction of the preset direction until the contrast of the projection image reaches the preset contrast threshold; If the contrast of the initial projection image is less than that of the second projection image, the driving motor is rotated by a preset small step value in the preset direction until the contrast of the projection image reaches the preset contrast threshold.

7. A film projection lamp using the electric focusing method according to any one of claims 1 to 6, characterized by It comprises a limiting decorative ring (1), a lens (2), a gear lens barrel (3), a bracket (4), a film (5), a light source assembly (6) and a focusing drive assembly (7); The bracket (4) is provided with a light outlet (41), and the film (5) covers the light outlet (41), and the outer periphery of the film (5) is provided with a lens barrel connecting ring (45); One end of the gear lens barrel (3) is located in the limiting decorative ring (1), the lens (2) is fixed at one end of the gear lens barrel (3), and the other end of the gear lens barrel (3) is threadedly connected with the lens barrel connecting ring (45); The focusing driving assembly (7) is arranged in the support (4), and is used for driving the gear lens barrel (3) to rotate, and the gear lens barrel (3) is used for driving the lens (2) to linearly displace along the optical axis direction in the limiting ring (1). The light source assembly (6) is arranged in the support (4), and is used for providing a light source, and the light emitted by the light source assembly (6) is emitted from the lens (2) after passing through the light outlet (41) and the film (5) in sequence.

8. The film projection lamp of claim 7, wherein, The support (4) is provided with a first groove (42), and the first groove (42) is used for mounting the film (5). The support (4) is provided with a second groove (43), and the second groove (43) is located in the first groove (42), and the light outlet (41) is located in the second groove (43). The second groove (43) is further provided with a positioning column (44), and the two positioning columns (44) are located on the two sides of the light outlet (41).

9. The film projection lamp of claim 8, wherein, The focusing driving assembly (7) comprises a motor (72) and a motor gear (71), and the support (4) is provided with a mounting groove (46) on the top. The motor (72) is arranged in the mounting groove (46), the motor gear (71) is connected with the motor (72), and the motor gear (71) is used for rotating under the driving of the motor (72) and driving the gear lens barrel (3) to rotate.

10. The film projection lamp of claim 9, wherein, The light source assembly (6) comprises a light source plate (61) and a light guide (62), and the light source plate (61) is provided with an LED lamp (63). The light source plate (61) is connected with the support (4), the light guide (62) penetrates through the light outlet (41), one end of the light guide (62) is arranged opposite to the LED lamp (63), the other end of the light guide (62) is arranged in the second groove (43), the other end of the light guide (62) is inserted into the positioning column (44), and the light emitted by the LED lamp (63) is emitted from the lens (2) after passing through the light guide (62), the light outlet (41) and the film (5) in sequence.

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