Imaging system using folded light path and vehicle-mounted VPA equipment
By employing a folded optical path imaging system in the vehicle-mounted VPA equipment, and using polarizing mirrors and quarter-wave plates to adjust the polarization state, light can be imaged on the windshield, solving the problems of complex optical paths and large equipment size, and achieving equipment miniaturization and improved imaging quality.
Patent Information
- Application Number
- CN202520168565.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-24
- Publication Date
- 2025-12-12
- Estimated Expiration
- 2035-01-24
AI Technical Summary
Existing vehicle-mounted VPA equipment has complex optical paths, large equipment size, poor imaging field of view, and affects the utilization of vehicle interior space.
A folded optical path imaging system is adopted, which uses a polarizer and a quarter-wave plate to adjust the polarization state, and the light is imaged on the windshield. This reduces the use of external polarizers in the optical path and achieves a reduction in the size of the optical path.
It improves the stereoscopic and levitation effect of the image, reduces the size of the device, avoids the generation of stray light, and improves the image quality.
Smart Images
Figure CN223664859U_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The utility model relates to the field of automobile intelligent driving technology especially, relates to an imaging system and vehicle VPA equipment of using folding light path. BACKGROUND
[0002] VPA (Vehicle Personal Assistant), namely vehicle intelligent assistant, is an intelligent voice interaction system integrated in the car, and in the automobile intelligent driving system, carrying VPA can greatly improve the sense of technology and improve user experience. The current VPA system generally uses negative refraction glass to image, and the design light path is simple, but the cost is higher and the image suspension is poor, the field of view is small, and due to the complex light path, the overall equipment volume is large, which affects the space utilization in the car. SUMMARY
[0003] The utility model provides a kind of imaging system and vehicle VPA equipment of using folding light path, to solve the problem of the light path of existing vehicle VPA equipment, equipment volume is big, and the problem of poor imaging field of view.
[0004] The utility model provides a kind of imaging system of using folding light path, including image source, first polaroscope, second polaroscope, quarter wave plate, first reflector and second reflector, the second polaroscope is located on the straight line light path of the image source, the linear polarized light of the image source is projected to the second polaroscope by the first polaroscope, the first reflector is located on the reflected light path of the second polaroscope, the second reflector is located on the reflected light path of the first reflector, windshield glass is located on the reflected light path of the second reflector, the reflected light of the second reflector is projected to the windshield glass by the second polaroscope, forms real image in the air after being reflected by the windshield glass, the quarter wave plate is located at the front end of the first reflector, and the incident light and the emergent light of the first reflector all pass through the quarter wave plate.
[0005] As a further improvement of the utility model, the image source is any one of TFT, LCOS and DLP image display system.
[0006] As a further improvement of the utility model, if the linear polarized light of the image source is S linear polarized light, the first polaroscope is reflected P linear polarized light, and transmits S linear polarized light, and the second polaroscope is reflected S linear polarized light, and transmits P linear polarized light.
[0007] As a further improvement of the utility model, if the linear polarized light of the image source is P linear polarized light, the first polaroscope is reflected S linear polarized light, and transmits P linear polarized light, and the second polaroscope is reflected P linear polarized light, and transmits S linear polarized light.
[0008] As a further improvement of the utility model, the linearly polarized light reflected by the second polarizer is converted from linearly polarized light to circularly polarized light after passing through the quarter-wave plate.
[0009] As a further improvement of the utility model, the circularly polarized light reflected by the first reflector is converted from circularly polarized light to linearly polarized light after passing through the quarter-wave plate.
[0010] As a further improvement of the utility model, the incident light rays with different incident angles produce the same phase delay on the quarter-wave plate.
[0011] As a further improvement of the utility model, if the linearly polarized light emitted by the image source is S linearly polarized light, it is converted to P linearly polarized light after passing through the quarter-wave plate for the second time; if the linearly polarized light emitted by the image source is P linearly polarized light, it is converted to S linearly polarized light after passing through the quarter-wave plate for the second time.
[0012] As a further improvement of the utility model, the light entrance surfaces of the first reflector and the second reflector are concave.
[0013] The utility model also provides a vehicle-mounted VPA equipment comprising an imaging system using a folded light path.
[0014] The utility model has the advantages that the traditional negative refraction glass imaging is adjusted to rely on windshield imaging, the image is more stereoscopic and has a floating feeling; the volume is reduced by using a folded light path; the polarizer and the quarter-wave plate are used in cooperation to adjust the polarization state, and stray light is not introduced under the premise of maintaining the normal operation of the light path system; the polarizer originally arranged outside the light path to adjust the light path is arranged inside the light path, and the folding of the light path is used to reduce the volume of the overall light path. BRIEF DESCRIPTION OF DRAWINGS
[0015] Figure 1 is the schematic diagram of the imaging system in the utility model.
[0016] Mark: 1-image source, 2-first polarizer, 3-second polarizer, 4-quarter-wave plate, 5-first reflector, 6-second reflector, 7-windshield, 8-real image, 9-human eye. DETAILED DESCRIPTION
[0017] In order to make the purpose, technical scheme and advantages of the utility model more clear and apparent, the utility model is further described in detail below by combining with the drawings and examples.
[0018] The utility model provides a kind of imaging system using folding optical path, including image source 1, first polaroscope 2, second polaroscope 3, quarter wave plate 4, first reflector 5 and second reflector 6, the second polaroscope 3 is located on the straight line light path of the image source 1, the linearly polarized light emitted by the image source 1 is projected to the second polaroscope 3 by the first polaroscope 2, the first reflector 5 is located on the reflected light path of the second polaroscope 3, the second reflector 6 is located on the reflected light path of the first reflector 5, windshield glass 7 is located on the reflected light path of the second reflector 6, the reflected light of the second reflector 6 is projected to the windshield glass 7 by the second polaroscope 3, forms real image 8 in the air after being reflected by the windshield glass 7, the quarter wave plate 4 is located at the front end of the first reflector 5, and the incident light and the emergent light of the first reflector 5 all pass through the quarter wave plate 4.
[0019] As Figure 1 The dotted line in the figure is optical path as shown, the utility model proposes a kind of imaging system using folding optical path, to realize the reduction of overall volume under the premise of ensuring VPA equipment imaging quality.The linearly polarized light emitted by image source 1 is reflected at second polaroscope 3 after passing through first polaroscope 2, reaches first reflector 5 after passing through quarter wave plate 4 after reflection;Reflects again from first reflector 5, reaches second reflector 6 for the second time after passing through quarter wave plate 4;Reflects for the third time at second reflector 6, emerges after passing through second polaroscope 3, and the light is reflected in the air by windshield glass 7, forms real image 8 that can be observed by human eye 9.
[0020] As an embodiment of the utility model, the image source 1 is any one of TFT, LCOS and DLP image display system.These systems have polarizer inside, and the light emitted by the polarizer is linearly polarized light.The incidence and emergence angle of the light of the system at windshield glass 7 is usually greater than 60 °, at this time, the reflectivity of windshield glass 7 to S linearly polarized light and P linearly polarized light is obviously different, and the reflectivity of S linearly polarized light is greater, and the energy utilization efficiency is higher.Therefore, the light emitted by image source 1 is usually S linearly polarized light, and it needs to be noted that since polarized reflection film can be added at windshield glass 7 to improve the reflectivity of corresponding linearly polarized light, so the type of linearly polarized light emitted by the image source 1 is not limited.
[0021] As another embodiment of the utility model, if the linearly polarized light emitted by the image source 1 is S linearly polarized light, the first polaroscope 2 reflects P linearly polarized light and transmits S linearly polarized light, and the second polaroscope 3 reflects S linearly polarized light and transmits P linearly polarized light.
[0022] As another embodiment of the present application, if the linearly polarized light emitted by the image source 1 is P linearly polarized light, the first polarizing mirror 2 reflects S linearly polarized light and transmits P linearly polarized light, and the second polarizing mirror 3 reflects P linearly polarized light and transmits S linearly polarized light. According to the linearly polarized light emitted by the image source 1, the types of the first polarizing mirror 2 and the second polarizing mirror 3 are selected, so that the light emitted by the image source 1 can pass through the first polarizing mirror 2 and be reflected at the second polarizing mirror 3.
[0023] As another embodiment of the present application, the linearly polarized light reflected from the second polarizing mirror 3 is converted from linearly polarized light to circularly polarized light after passing through the quarter-wave plate 4.
[0024] As another embodiment of the present application, the circularly polarized light reflected from the first mirror 5 is converted from circularly polarized light to linearly polarized light after passing through the quarter-wave plate 4.
[0025] As another embodiment of the present application, the incident light with different incident angles produces the same phase delay on the quarter-wave plate 4.
[0026] As another embodiment of the present application, if the linearly polarized light emitted by the image source 1 is S linearly polarized light, it is converted to P linearly polarized light after passing through the quarter-wave plate 4 for the second time; if the linearly polarized light emitted by the image source 1 is P linearly polarized light, it is converted to S linearly polarized light after passing through the quarter-wave plate 4 for the second time.
[0027] As another embodiment of the present application, the light entrance surfaces of the first mirror 5 and the second mirror 6 are concave. The first mirror 5 and the second mirror 6 can use any one of the mirrors including but not limited to spherical, aspherical, free-form surface types.
[0028] The following is an example of the image source 1 emitting S linearly polarized light. The S linearly polarized light emitted by the image source 1 reaches the first polarizer 2, which is a polarizing lens that transmits S linearly polarized light and reflects P linearly polarized light. The light passes through the first polarizer 2 without any change. The light that passes through the first polarizer 2 reaches the second polarizer 3. The second polarizer 3 is a polarizing lens that transmits P linearly polarized light and reflects S linearly polarized light. The S linearly polarized light is reflected when it reaches the second polarizer 3. The light reflected by the second polarizer 3 is S linearly polarized light, which continues to propagate in the direction of the quarter-wave plate 4. When the S linearly polarized light passes through the quarter-wave plate 4 located at the front end of the first mirror 5, the polarization state changes. In an ideal state, the light is perpendicular to the quarter-wave plate 4, and the angle between the principal axis of the quarter-wave plate 4 and the S linearly polarized light is 45°, causing a phase delay of one-quarter wavelength. The light is converted from S linearly polarized light to circularly polarized light (left-handed or right-handed circularly polarized light). If the light is not perpendicular to the quarter-wave plate 4, the phase delay value will deviate, causing the S linearly polarized light to be converted to elliptically polarized light. Therefore, the quarter-wave plate 4 should have good performance to ensure that the incident light within a certain range of incident angles produces the same phase delay. The circularly polarized light continues to propagate and reaches the first mirror 5, where it is reflected again and passes through the quarter-wave plate 4. The phase of the light is delayed by one-quarter wavelength for the second time, and the total phase delay is one-half wavelength, converting the light from the S linearly polarized light originally emitted from the image source 1 to P linearly polarized light. The second polarizer 3 is a polarizing lens that transmits P linearly polarized light and reflects S linearly polarized light. The S linearly polarized light is reflected when it reaches the second polarizer 3. The P linearly polarized light that passes through the quarter-wave plate 4 continues to propagate towards the second mirror 6, where it is reflected. The P linearly polarized light reflected by the second mirror 6 can normally pass through the second polarizer 3, which transmits P linearly polarized light and reflects S linearly polarized light, and then reflect on the windshield 7 to form a real image 8 that can be observed by the human eye 9 in the air. If the image source 1 emits P linearly polarized light, the first polarizer 2 is changed to reflect S linearly polarized light and transmit P linearly polarized light, and the second polarizer 3 is changed to reflect P linearly polarized light and transmit S linearly polarized light.
[0029] If the performance of the quarter-wave plate 4 is general and cannot guarantee the consistency of the phase delay of the incident light in a certain range of incident angles, the S-line polarized light here will not be pure P-line polarized light, but also contains a small amount of P-line polarized light component, which may become stray light through the second polarizer 3 and affect the final imaging effect. At the same time, the larger the incident angle, the greater the phase delay deviation, which will also cause the loss of a certain light in the final imaging, and the problem of reduced picture brightness and uneven brightness. Therefore, the quarter-wave plate 4 selected needs to ensure the same phase delay for light in a wide range of incident angles, and needs to cover the use range of the first reflector 5 to ensure the consistency of the image and avoid image misalignment.
[0030] The utility model further provides a kind of vehicle-mounted VPA equipment, and the equipment has adopted above imaging system.
[0031] The above content is a further detailed description of the utility model in combination with specific preferred embodiments, and cannot be determined that the specific implementation of the utility model is limited to these descriptions. For ordinary skilled persons in the technical field to which the utility model belongs, without departing from the concept of the utility model, a number of simple deductions or substitutions can also be made, which should be regarded as belonging to the protection scope of the utility model.
Claims
1. An imaging system using a folded optical path, characterized in that, The system includes an image source, a first polarizer, a second polarizer, a quarter-wave plate, a first reflector, and a second reflector. The second polarizer is located in the straight optical path of the image source. Linearly polarized light emitted from the image source is projected onto the second polarizer through the first polarizer. The first reflector is located in the reflected optical path of the second polarizer, and the second reflector is located in the reflected optical path of the first reflector. The windshield is located in the reflected optical path of the second reflector. The reflected light from the second reflector is projected onto the windshield through the second polarizer and forms a real image in the air after reflection by the windshield. The quarter-wave plate is located in front of the first reflector, and both the incident and outgoing light rays from the first reflector pass through the quarter-wave plate.
2. An imaging system using a folded optical path according to claim 1, characterized in that, The image source can be any one of TFT, LCOS, and DLP image display systems.
3. An imaging system using a folded optical path according to claim 1, characterized in that, If the linearly polarized light emitted by the image source is S-polarized light, the first polarizing mirror reflects P-polarized light and transmits S-polarized light, and the second polarizing mirror reflects S-polarized light and transmits P-polarized light.
4. An imaging system using a folded optical path according to claim 1, characterized in that, If the linearly polarized light emitted by the image source is P-polarized light, the first polarizing mirror reflects S-polarized light and transmits P-polarized light, and the second polarizing mirror reflects P-polarized light and transmits S-polarized light.
5. An imaging system using a folded optical path according to claim 1, characterized in that, The linearly polarized light reflected from the second polarizing mirror is converted from linearly polarized light to circularly polarized light after passing through the quarter-wave plate.
6. An imaging system using a folded optical path according to claim 1, characterized in that, The circularly polarized light reflected from the first mirror is converted to linearly polarized light after passing through the quarter-wave plate.
7. An imaging system using a folded optical path according to claim 1, characterized in that, Light rays incident at different angles produce the same phase delay on the quarter-wave plate.
8. An imaging system using a folded optical path according to claim 1, characterized in that, If the linearly polarized light emitted by the image source is S-polarized light, it will be converted into P-polarized light after passing through the quarter-wave plate for the second time; if the linearly polarized light emitted by the image source is P-polarized light, it will be converted into S-polarized light after passing through the quarter-wave plate for the second time.
9. An imaging system using a folded optical path according to claim 1, characterized in that, The light-incident surfaces of both the first and second reflectors are concave.
10. A vehicle-mounted VPA device, characterized in that, An imaging system using a folded optical path, as described in any one of claims 1-9.