Projection structure, projection method, medium and vehicle

Technical Field

The present invention relates to the technical field of projection, in particular to a projection structure, a projection method, a medium and a vehicle.

Background Art

As motor vehicle technology develops, projection lamps are being used in vehicles on an ever wider scale. For example, they can be installed at vehicle doors, rear view mirrors, etc., projecting a variety of patterns on the ground around the vehicle body or within the motor vehicle. They not only provide an illuminating function but can also serve to indicate information.

In the prior art, Chinese patent CN111323995A has disclosed a projection structure, in which a dynamic projection is achieved by an electric motor driving a film part to rotate. However, because the electric motor exhibits error during operation, e.g. error in the step angle of a stepper motor, a projection pattern on the film part cannot be projected at the same position during consecutive projection, so the user will observe movement of the projection pattern on the projection surface, resulting in a poor experience. Summary of the Invention

Therefore, an objective of the present invention is to propose a projection structure, projection method, medium and system that can at least partially solve the above-mentioned problem.

According to one aspect of the present invention, a projection structure is provided, comprising a light source, a film part, a lens set, an electric motor and a sensor module, wherein: the light source can emit light rays towards the film part ; the film part is located between the light source and the lens set, and comprises multiple projection patterns, the projection patterns being able to at least partially transmit light rays from the light source; the lens set comprises at least one lens, for projecting at least a portion of transmitted light rays from the film part, to project the projection patterns onto a projection surface ; the electric motor can drive the film part to rotate to perform consecutive projection; the film part further comprises multiple identification codes, the identification codes being in one-to-one correspondence with the projection patterns, and used to indicate position information of the corresponding projection patterns ; the intervals at which the multiple identification codes are arranged are the same as the intervals at which the multiple projection patterns are arranged; the sensor module can detect information relating to the identification code, the information being able to uniquely determine the position of the identification code.

According to the embodiments of the present invention, providing the identification codes on the film part and using the sensor module to detect information relating to the identification codes makes it easier to correct the positions of two consecutive projections, so that the two consecutive projections are located at substantially the same position.

In one embodiment, the sensor module comprises an optical sensor, and the information relating to the identification code comprises the amount of light transmitted by the identification code.

In one embodiment, the amount of light transmitted by the identification code progressively increases or progressively decreases in the direction of rotation of the identification code.

According to the embodiments of the present invention, configuring the amount of light transmitted by the identification code to progressively increase or progressively decrease in the direction of rotation of the identification code can ensure that the amount of light transmitted by the identification code can uniquely identify the position of the identification code.

In one embodiment, the identification code comprises a triangular identification code.

According to the embodiments of the present invention, the amount of light transmitted by the triangular identification code progressively increases or progressively decreases in the direction of rotation thereof, so it can be ensured that the amount of light transmitted by the identification code can uniquely identify the position of the identification code.

In one embodiment, the sensor module comprises a magnetic force sensor, and the information relating to the identification code comprises a magnetic force between the identification code and the magnetic force sensor.

According to the embodiments of the present invention, the magnetic force will be smaller when the identification code is further away from the magnetic force sensor, and conversely will be larger when the identification code is closer to the magnetic force sensor; thus, the magnetic force between the identification code and the magnetic force sensor can uniquely identify the position of the identification code.

In one embodiment, the electric motor is a stepper motor.

According to another aspect of the present invention, a projection method for any one of the projection structures described above is also provided; for two consecutive projections, the method comprises: acquiring first information of a first identification code during a preceding projection period, the first information being used to indicate information of a stop position of a first projection pattern corresponding to the first identification code; acquiring second information of a second identification code during a following projection period, the second information being used to indicate position information of a second projection pattern corresponding to the second identification code; if the absolute value of the difference between the first information and the second information is greater than or equal to a threshold, determining calibration information based on the first information and the second information; driving the electric motor to rotate based on the calibration information, so that the position of the second projection pattern is closer to the stop position of the first projection pattern during the preceding projection period.

According to the embodiments of the present invention, for two consecutive projections, information relating to the identification codes is used to correct the projection position of the following projection, so that the following projection is located at substantially the same position as the preceding projection.

In one embodiment, the step of determining calibration information based on the first information and the second information comprises: determining a rotation direction of the electric motor based on a size relationship of the first information and the second information.

According to an embodiment of the present invention, the size relationship of the first information and the second information reflects position relationship of the first identification code and the second identification code, and it is thereby possible to determine a rotation direction of the electric motor.

In one embodiment, the step of driving the electric motor to rotate based on the calibration information comprises: driving the electric motor to rotate through a predetermined angle in said rotation direction.

According to the embodiments of the present invention, driving the electric motor to rotate through a predetermined angle can bring the position of the following projection closer to the position of the preceding projection. If the electric motor rotation angle is preset, multiple corrections might be needed in order to make the absolute value of the difference between the first information and second information less than the threshold.

In one embodiment, the step of determining calibration information based on the first information and the second information further comprises: determining a rotation angle of the electric motor based on the first information and the second information.

According to the embodiments of the present invention, directly determining the angle of electric motor rotation enables the position of the following projection to approach the position of the preceding projection more quickly.

In one embodiment, acquiring first information of a first identification code comprises receiving information relating to the amount of light transmitted by the first identification code from an optical sensor; and acquiring second information of a second identification code comprises receiving information relating to the amount of light transmitted by the second identification code from the optical sensor.

In one embodiment, acquiring first information of a first identification code comprises receiving information relating to a magnetic force of the first identification code from a magnetic force sensor; and acquiring second information of a second identification code comprises receiving information relating to a magnetic force of the second identification code and measured by the magnetic force sensor.

According to another aspect of the present invention, a machine-readable medium is also provided, the medium having instructions stored thereon which, when run on the machine, cause the machine to perform any one of the projection methods described above.

According to another aspect of the present invention, a vehicle is also provided, comprising any one of the projection structures described above.

Brief Description of the Figures

The abovementioned characteristics, technical features, advantages and modes of implementation of the present invention are explained further below in a clear and easy- to-understand manner by giving a description of preferred embodiments with reference to the drawings, wherein

Fig. 1 shows a three-dimensional structural schematic drawing of a projection structure in the prior art.

Fig. 2 shows a structural schematic drawing of a film part 3 according to an embodiment of the present invention.

Fig. 3 shows a rotational schematic drawing of an identification code 320 according to an embodiment of the present invention. Fig. 4 shows a flow chart of a projection method according to an embodiment of the present invention.

Detailed Description of Embodiments

Embodiments of the present invention are described demonstratively below. As those skilled in the art should realise, the embodiments described may be amended in various ways without departing from the concept of the present invention. Thus, the drawings and description are essentially illustrative, not restrictive. In the following text, identical reference numerals generally denote elements with identical or similar functions.

As the foundation which the present invention improves upon, Chinese patent CN111323995A has disclosed a projection structure. Some of the content of that patent is cited here, and the patent document thereof may be referred to for detailed information. Fig. 1 shows a three-dimensional structural schematic drawing of the projection structure disclosed in that patent. As shown in the figure, the projection structure comprises a first support 1, a lens set 2, a film part 3, a light source 4, an electric motor 5, a transmission part 7 and a second support 8, wherein the light source 4, the film part 3 and the lens set 2 form a projection light path. Specifically, the light source 4 can emit light rays towards the film part 3; the film part 3 is located between the light source 4 and the lens set 2, and comprises a flywheel and film. The film can be loaded on the flywheel, which has holes for light rays to pass through, so that light rays from the light source 4 can pass through the holes and shine on corresponding positions on the film. The lens set 2 comprises at least one lens accommodated in the first support 1, and the second support 8 is configured to support the first support 1, wherein the first support 1 and second support 8 have a first space and a second space respectively for accommodating the film part 3. The transmission mechanism 7 is configured to connect the electric motor 5 and the film part 3, such that the film part 3 is driven to rotate by the electric motor 5 via the transmission mechanism 7.

As shown in Fig. 1, the projection structure further comprises a sensor module 601, for obtaining initial position information of the film, etc. Furthermore, the projection structure may comprise a control part, for receiving input information from the sensor module 601, to control the light source 4 and the drive electric motor 5.

In the projection structure described above, because of error during operation of the electric motor 5, a projection pattern on the film part 3 cannot be projected at the same position during consecutive projection, so the user will observe movement of the projection pattern on the projection surface, resulting in a poor experience. Thus, the embodiments of the present invention make improvements to the film part 3 and the projection method, and this is described in detail below with reference to the drawings.

Fig. 2 shows a structural schematic drawing of a film part 3 according to an embodiment of the present invention. As shown in the figure, the film part 3 is disc-shaped, and comprises multiple projection patterns 310 and multiple identification codes 320, wherein the projection patterns 310 can at least partially transmit light rays from the light source 4, and at least a portion of the transmitted light rays can be projected through the lens set 2, to finally project the projection patterns 310 onto a projection surface. The identification codes 320 are in one-to-one correspondence with the projection patterns 310, and used to indicate position information of the corresponding projection patterns. For example, as shown in Fig. 2, identification code 321 corresponds to projection pattern 311, and is used to indicate position information of projection pattern 311; identification code 322 corresponds to projection pattern 312, and is used to indicate position information of projection pattern 312.

As shown in Fig. 2, the projection patterns 310 and identification codes 320 are arranged alternately at edge positions of the film part 3, and the intervals at which the identification codes 320 are arranged are the same as the intervals at which the projection patterns 310 are arranged. This means that ideally, when identification code 321 rotates to the current position of identification code 322, projection pattern 311 will also rotate to the current position of projection pattern 312. Thus, by causing the identification code of a projected pattern of a preceding projection and the identification code of a projected pattern of a following projection to be located at substantially the same position, it can be ensured that the projected patterns of these two projections are located at substantially the same position. It will be understood that the projection patterns 310 and identification codes 320 are not restricted to being arranged alternately. For example, the identification codes 320 could also be arranged at an outer side of the projection patterns 310 in a radial direction of the film part 3.

The electric motor 5 can drive the film part 3 to rotate to achieve consecutive projection. Here, consecutive projection may mean sequentially projecting multiple projection patterns 310 arranged consecutively on the film part 3, or may mean sequentially projecting multiple projection patterns 310 arranged at intervals on the film part 3. During consecutive projection, the identification codes corresponding to the projected patterns will pass the sensor module 601 sequentially, and the sensor module 601 can detect information relating to the identification codes; this information may be a function of identification code position, and there is a one-to-one mapping therebetween, i.e. the identification code position can be uniquely determined from the information.

The position of the sensor module 601 may be as shown in Fig. 1, not located between the light source 4 and the lens set 2. In this case, the projected pattern and the identification code thereof are different from the projection pattern and the identification code thereof which pass the sensor. Because the projection patterns are arranged at the same intervals as the identification codes, the identification code passing the sensor may also be used to indirectly correct the position of the projected pattern. The position of the sensor module 601 may also be located between the light source 4 and the lens set 2. In this case, the projected pattern and the identification code thereof are the same as the projection pattern and the identification code thereof which pass the sensor, and the identification code of the projected pattern may be used to correct the position of the projected pattern directly.

In one example, the sensor module 601 may comprise an optical sensor, comprising a light emitting element and a light receiving element. The light emitting element can emit light rays towards the light receiving element; the light rays may be visible light, infrared light, laser light or any other suitable light rays. Because the projected light rays are visible light, infrared light is preferably used here, to avoid interference between the projected light rays and the light rays emitted by the light emitting element. The identification code 320 can rotate to a position between the light emitting element and the light receiving element, and the identification code 320 can at least partially transmit light rays from the light emitting element; the transmitted light rays reach the light receiving element, and the sensor module 601 can thus detect the amount of light transmitted by the identification code. To enable the amount of light transmitted by the identification code 320 to uniquely determine the position of the identification code 320, the amount of light transmitted by the identification code 320 should progressively increase or progressively decrease in the rotation direction of the identification code 320. For example, but without limitation, as shown in Figs. 2 and 3, the identification code 320 may be a triangular identification code. As the identification code 320 rotates anticlockwise in direction F, it sequentially passes position A, position B and position C. Thus, the amount of light transmitted by the identification code 320 at position A (the shaded region) is smallest, and the amount of light transmitted at position C (the shaded region) is largest, i.e. the amount of light transmitted progressively increases. It will be understood that the identification code may also have any other suitable shape, as long as the amount of light that it transmits meets the above condition.

In another example, the sensor module 601 may comprise a magnetic force sensor, the identification code 320 may be a magnetic element, and the magnetic force sensor can measure a magnetic force generated by the identification code 320. To enable the magnetic force of the identification code 320 to uniquely determine the position of the identification code 320, it should be ensured that the stop position of each identification code 320 during a projection period is located at one side of the sensor module 601.

It will be understood that the sensor module 601 is not limited to the above example, and may be any other suitable type of sensor.

Furthermore, in the embodiments of the present invention, the electric motor 5 is preferably a stepper motor, and the step angle of the electric motor can be set to be divisible by the angular distance between projection patterns. Of course, the electric motor 5 may also be of any other suitable type.

The embodiments of the present invention further provide a projection method for the projection structure described above. As shown in Fig. 4, for two consecutive projections, the projection method comprises:

SI: during a preceding projection period, first information of a first identification code is acquired, the first information being used to indicate information of a stop position of a first projection pattern corresponding to the first identification code.

Here, the projection period refers to the time from the end of one projection to the end of the next projection. In one example, acquiring the first information of the first identification code may comprise receiving information relating to the amount of light transmitted by the first identification code from the optical sensor, wherein the information relating to the amount of light transmitted by the first identification code may comprise an electrical signal associated with the amount of light transmitted, e.g. a current or voltage signal. In another example, acquiring the first information of the first identification code may comprise receiving information relating to the magnetic force of the first identification code from the magnetic force sensor.

As stated above, the first identification code may be the identification code of the projection pattern that will be projected during the preceding projection period, or may be the identification code of the projection pattern that passes the sensor module during the preceding projection period.

S2: during a following projection period, second information of a second identification code is acquired, the second information being used to indicate position information of a second projection pattern corresponding to the second identification code.

In one example, acquiring the second information of the second identification code may comprise receiving information relating to the amount of light transmitted by the second identification code from the optical sensor, wherein the information relating to the amount of light transmitted by the second identification code may comprise an electrical signal associated with the amount of light transmitted, e.g. a current or voltage signal. In another example, acquiring the second information of the second identification code may comprise receiving information relating to the magnetic force of the second identification code from the magnetic force sensor.

As stated above, the second identification code may be the identification code of the projection pattern that will be projected during the following projection period, or may be the identification code of the projection pattern that passes the sensor module during the following projection period.

The second identification code may be adjacent to the first identification code, or may be separated therefrom by another identification code.

S3: the absolute value of the difference between the first information and second information is calculated, and compared with a threshold; if the absolute value is greater than or equal to the threshold, S4 is performed, and if the absolute value is less than the threshold, S5 is performed. Here, the threshold may be preset as required. S4: based on the first information and second information, calibration information is calculated, and the electric motor is driven to rotate based on the calibration information, so that the position of the second projection pattern is closer to the stop position of the first projection pattern during the preceding projection period.

In one example, determining calibration information based on the first information and second information comprises determining a direction of electric motor rotation based on the first information and second information. Specifically, for example, if the information relating to the identification code progressively increases as the film part rotates anticlockwise, then if the second information is larger than the first information, the calibration information should comprise information causing the electric motor to rotate clockwise, and conversely, if the second information is smaller than the first information, the calibration information should comprise information causing the electric motor to rotate anticlockwise. Driving the electric motor to rotate based on the calibration information may comprise driving the electric motor to rotate through a predetermined angle in the determined rotation direction. The predetermined angle may be preset according to requirements, for example but without limitation, set to the step angle of the electric motor. In this case, after the electric motor has rotated, the absolute value of the difference between the second information and first information might still be greater than or equal to the threshold, so S3 and S4 need to be performed multiple times until the difference is less than the threshold.

In another example, determining calibration information based on the first information and second information further comprises determining an angle of electric motor rotation based on the first information and second information. If the relationship between the information relating to the identification code and the position of the identification code is determined in advance, then position information of the first identification code can be determined according to the first information, position information of the second identification code can be determined according to the second information, and an electric motor rotation angle can then be determined according to a position difference between the first identification code and second identification code; alternatively, a position difference between the first identification code and second identification code can be determined directly according to the difference between the first information and second information, and an electric motor rotation angle can thereby be determined. Furthermore, it is also possible, based on a determined relationship between the position difference between identification codes and the electric motor rotation angle, to determine in advance a relationship between the difference between items of information relating to identification codes and the electric motor rotation angle, and it is thereby possible to determine the electric motor rotation angle directly according to the difference between the first information and second information.

S5: control information is sent to the light source to light up the light source, and a projection pattern is thereby projected.

For example without limitation, the projection method described above is implemented by the abovementioned control part.

In the embodiments of the present invention, unique identification codes are provided on the film part of the projection structure, and the identification codes can be used to cause the projected patterns of two consecutive projections to stop at substantially the same positions.

The embodiments of the present invention further provide a machine-readable medium, having instructions stored thereon which, when run on a machine, cause the machine to perform the projection method described above.

The embodiments of the present invention further comprise a vehicle, comprising the projection structure described above.

The present invention is not limited to the structure described above; various other variants could also be used. Although the present invention has already been described by means of a limited number of embodiments, those skilled in the art could, drawing benefit from this disclosure, design other embodiments which do not depart from the scope of protection of the present invention disclosed herein. Thus, the scope of protection of the present invention should be defined by the attached claims alone.