Low-blue-light eye-care head-up display optical system

Abstract

The utility model discloses a kind of low blue light eye protection head-up display optical systems belonging to head-up display technical field, including head-up display body, backlight module, the backlight module is used to emit light source to the head-up display body, the backlight module includes lamp plate, blue light chip, low blue light LED lamp pearl, several blue light chips are equipped on the lamp plate, each The blue light chip is connected with low blue light LED lamp, phosphor, the phosphor is used to cooperate with blue light chip, the luminous wavelength of the blue light chip moves to 457.5-465nm, the blue light chip is excited phosphor with 457.5-465nm to form white light.The utility model selects 457.5-465nm long wave blue light in blue light chip terminal, excludes traditional 415-455nm short wave harmful blue light, better adaptation head-up display eye entry luminance, reduce the high brightness eye entry defect of outdoor strong light environment, to more optimal protection human eye retina.

Description

Technical Field

[0001] This utility model belongs to the field of head-up display technology and relates to a low blue light eye-protection head-up display optical system. Background Technology

[0002] A Head-Up Display (HUD) works by projecting important driving information, such as speed and navigation, onto a suitable position on the windshield using a designed optical path. This creates a virtual image of the target information for the driver to view, eliminating the need to look down at the instrument panel and increasing driving safety.

[0003] Currently, compared to similar in-vehicle displays, traditional HUDs have an eye brightness that is more than 10 times higher. Under such high brightness, the 415-455nm short-wavelength LEDs used in the backlight of HUDs contain harmful blue light, which is very damaging to the human retina.

[0004] Furthermore, existing HUDs on the market use LED chips with blue light in the 447.5-455nm wavelength range for backlighting, but they still contain some harmful blue light in the 415-455nm short wavelength range. This proportion exceeds the standard TÜV Rheinland eye protection specifications, which require that the light radiation energy in the 415-455nm range should account for less than 50% of the total light radiation energy in the 400-500nm range. Moreover, HUDs are used in outdoor environments with strong light. To see the content displayed on a HUD clearly, the brightness required to reach the eyes should be greater than 12,000 nits, far exceeding the brightness value of similar automotive display devices (the brightness of automotive displays is generally around 1,000 nits). Thus, long-term use poses a risk of damage to the human retina. Utility Model Content

[0005] This invention provides a low blue light eye-protecting head-up display optical system, which aims to solve the problem that the backlight LEDs used in existing HUDs still contain some harmful blue light radiation bands, have high brightness, and pose a risk of damage to the human retina with long-term use.

[0006] To achieve the above objectives, this utility model provides a low blue light eye-protection head-up display optical system, comprising:

[0007] Heads up to display the main body;

[0008] A backlight module is used to emit a light source to the head-up display body. The backlight module includes a lamp board, a blue light chip, and low blue light LED beads. The lamp board is provided with a plurality of blue light chips, and each blue light chip is connected to a low blue light LED.

[0009] Phosphor, which is used in conjunction with a blue light chip, wherein the emission wavelength of the blue light chip is shifted upward to 457.5-465nm, and the blue light chip excites the phosphor at 457.5-465nm to form white light.

[0010] Preferably, the blue light chip may also contain white light formed by a mixture of red, green and blue light.

[0011] Preferably, the wavelength of the red light is 620-660nm, the wavelength of the green light is 520-560nm, and the wavelength of the blue light is 470-490nm.

[0012] Preferably, the head-up display body includes a first reflector, a second reflector, a windshield, a virtual image surface, and a human eye. The backlight module is located below the first reflector. The backlight module emits a light source that is projected onto the first reflector. The first reflector reflects the light source onto the second reflector. The second reflector reflects the light source onto the windshield. The light source is reflected by the windshield and enters the human eye. The human eye obtains the virtual image surface through the windshield. The virtual image surface is located on the outside of the windshield.

[0013] Preferably, the blue light chips on the lamp board are arranged in a 3-row, 4-column layout.

[0014] The advantages of this utility model over the prior art are:

[0015] This invention provides a low blue light eye-protecting head-up display optical system. By selecting 457.5-465nm long-wavelength blue light at the blue light chip terminal, it eliminates the harmful 415-455nm short-wavelength blue light, better adapts to the brightness of the head-up display entering the eye, reduces the high brightness entering the eye defect in strong outdoor light environment, and thus better protects the human retina.

[0016] To more clearly illustrate the structural features and effects of this utility model, the following detailed description of this utility model is provided in conjunction with the accompanying drawings and specific embodiments. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the light source reflection of this utility model;

[0018] Figure 2 This is a schematic diagram of the lamp panel structure of this utility model;

[0019] Figure 3 This is a comparison chart of the brightness values ​​of low blue light LED wavelengths and ordinary blue light LED wavelengths.

[0020] Figure 4 This is a comparison chart of the color gamut of low blue light LEDs and the color gamut of ordinary blue light LEDs.

[0021] Figure label:

[0022] 1. Backlight module; 2. First reflector; 3. Second reflector; 4. Virtual image plane; 5. Windshield; 6. Human eye; 7. Low blue light LED beads; 8. Light board. Detailed Implementation

[0023] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used herein in the specification of the application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having," and any variations thereof, in the specification, claims, and foregoing drawings of this application are intended to cover non-exclusive inclusion. The terms "first," "second," etc., in the specification, claims, or foregoing drawings of this application are used to distinguish different objects, not to describe a particular order.

[0024] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0025] To achieve the above objectives, this utility model provides a low blue light eye-protection head-up display optical system, referenced... Figure 1-4 As shown, it includes:

[0026] Heads up to display the main body;

[0027] A backlight module is used to emit a light source to the head-up display body. The backlight module includes a lamp board, a blue light chip, and low blue light LED beads. The lamp board is provided with a plurality of blue light chips, and each blue light chip is connected to a low blue light LED.

[0028] Phosphor, which is used in conjunction with a blue light chip, wherein the emission wavelength of the blue light chip is shifted upward to 457.5-465nm, and the blue light chip excites the phosphor at 457.5-465nm to form white light.

[0029] In this embodiment, low blue light means controlling the radiation intensity or proportion of short-wavelength blue light with a wavelength of 415-455nm within a safe range that complies with relevant international / national standards (such as TÜV Rheinland certification) and does not have a significant negative impact on human physiological rhythms or visual health.

[0030] Among them, TÜV Rheinland's eye protection specification requires a blue light ratio of less than 50%, and the calculation formula is as follows:

[0031] ;

[0032] In the formula, Blue light ratio represents the proportion of harmful blue light in the 415-455nm range to the blue light band in the 400-500nm range, and E(λ) represents the actual blue light irradiance at a certain wavelength λ (unit: W / (m²・nm)), which is measured by a spectrometer, and λ represents the wavelength.

[0033] Because the blue light chip used in traditional HUD backlight modules emits light in wavelengths concentrated in the 447.5-465nm range, it still contains a large amount of harmful short-wavelength blue light in the 415-455nm range. Its light radiation energy often accounts for more than 50% of the total energy in the 400-500nm range. Therefore, traditional HUDs do not meet the TÜV Rheinland eye protection specifications.

[0034] In this embodiment, the blue light chip is the core component for achieving the low blue light effect. In terms of chip manufacturing process, the emission wavelength of the blue light chip is shifted upward to 457.5-465nm. This wavelength range completely avoids the short-wavelength harmful blue light band of 415-455nm, greatly reducing the energy of harmful blue light photons. The blue light chip excites phosphors to form white light at 457.5-465nm. The process modification is small, the cost is low, and the impact on brightness is minimal.

[0035] Furthermore, the blue light chip can also contain white light formed by mixing red, green, and blue light. The wavelength of the red light is 620-660nm, the wavelength of the green light is 520-560nm, and the wavelength of the blue light is 470-490nm. The blue light chip forms white light by mixing the three primary colors of red, green, and blue light, without the need for phosphors. It retains the long-wavelength blue light that has less impact on human physiological rhythms, while ensuring the color rendering and brightness requirements of white light, making it better suited for outdoor environments.

[0036] The connection between the low blue light LED beads and the blue light chip adopts a eutectic bonding process. This connection method can improve the heat conduction efficiency, avoid wavelength shift caused by high temperature, and ensure luminous stability. According to actual measurement, the light radiation energy of the 415-455nm band of the low blue light LED beads is less than 30%, which is far better than the 50% threshold requirement of TÜV Rheinland.

[0037] Furthermore, the head-up display body includes a first reflector, a second reflector, a windshield, a virtual image surface, and a human eye. The backlight module is located below the first reflector. The backlight module emits a light source that is projected onto the first reflector. The first reflector reflects the light source onto the second reflector. The second reflector reflects the light source onto the windshield. The light source is reflected by the windshield and enters the human eye. The human eye obtains the virtual image surface through the windshield. The virtual image surface is located on the outside of the windshield.

[0038] In this embodiment, the light board is made of PCB substrate, and the blue light chips on it adopt a matrix layout of 3 rows and 4 columns, with a total of 12 blue light chips and matching low blue light LED beads, to achieve uniform distribution of backlight source and avoid uneven display image caused by local brightness differences. Compared with the traditional random arrangement or single row arrangement, the regular layout of 3 rows and 4 columns can make the light intensity distribution when the light source is projected onto the reflector more uniform. After multiple reflections, the brightness of the light entering the human eye is more consistent, reducing the fatigue caused by brightness fluctuations to the human eye. It is suitable for the miniaturized installation requirements of mainstream vehicle HUDs and does not require major modifications to the internal structure of the HUD body.

[0039] Taking the HUD system of a family sedan as an example, this utility model's low blue light eye-protection head-up display optical system is assembled and applied. During vehicle operation, after the driver activates the HUD system, the low blue light LED beads of the backlight module are powered on and emit light. The blue light chip emits long-wavelength blue light (457.5-465nm), which is excited by phosphors to produce a white light source, or a mixture of red, green, and blue light can be used to form a white light source. The light source is reflected by a first reflector to a second reflector, and after the light path is adjusted by curved surface reflection, it is projected onto the windshield and finally reflected into the driver's eyes. The driver sees a clear virtual image on the outside of the windshield, displaying driving information such as speed, navigation guidance, and distance to the vehicle ahead.

[0040] Under strong midday sunlight (ambient light intensity of approximately 100,000 nits), the HUD system maintained an eye brightness of 13,000 nits, allowing the driver to clearly read information without significant glare. After a two-hour continuous driving test, the driver did not experience any symptoms of eye fatigue such as dryness or itchiness. Testing with professional light radiation detection equipment showed that the system's 415-455nm short-wavelength blue light radiation energy accounted for 28%, meeting the TÜV Rheinland RG0 no-hazard level requirements, achieving a balance between high brightness display and eye protection.

[0041] like Figure 3The figure shows a comparison of the brightness values ​​of low blue light LED wavelengths and ordinary light LED wavelengths. The 450 nm wavelength corresponds to the curve of ordinary light LED, represented by line 10, while the 460 nm wavelength corresponds to the curve of low blue light LED, represented by line 9. The brightness of low blue light LED reaches its peak at a wavelength of 460 nm.

[0042] like Figure 4 The image shows a comparison of the color gamut of low-blue-light LEDs and ordinary-blue-light LEDs. The vertex position on the X-axis represents the color gamut position of the ordinary-blue-light LED (line 11), while the position slightly below the vertex represents the color gamut position of the low-blue-light LED (line 12). Figure 4 As can be seen, the color gamut of low blue light LEDs is not much different from that of ordinary LEDs, indicating that low blue light LEDs have little impact on the color gamut.

[0043] In summary, this utility model provides a low blue light eye-protecting head-up display optical system. By selecting 457.5-465nm long-wavelength blue light at the blue light chip terminal, it eliminates the harmful 415-455nm short-wavelength blue light, better adapts to the brightness of the head-up display entering the eye, reduces the high brightness entering the eye defect in strong outdoor light environments, and thus better protects the human retina.

[0044] The technical principles of this utility model have been described above with reference to specific embodiments, which are merely preferred embodiments of this utility model. The protection scope of this utility model is not limited to the above embodiments; all technical solutions falling within the scope of this utility model's concept are protected. Other specific embodiments of this utility model that can be conceived by those skilled in the art without creative effort will also fall within the protection scope of this utility model.

Claims

1. A low blue light eye-protection head-up display optical system, characterized in that, include: Heads up to display the main body; A backlight module is used to emit a light source to the head-up display body. The backlight module includes a lamp board, a blue light chip, and low blue light LED beads. The lamp board is provided with a plurality of blue light chips, and each blue light chip is connected to a low blue light LED. Phosphor, which is used in conjunction with a blue light chip, wherein the emission wavelength of the blue light chip is shifted upward to 457.5-465nm, and the blue light chip excites the phosphor at 457.5-465nm to form white light.

2. The low blue light eye-protection head-up display optical system according to claim 1, characterized in that, The blue light chip may also contain white light formed by a mixture of red, green and blue light.

3. The low blue light eye-protection head-up display optical system according to claim 2, characterized in that, The wavelength of the red light is 620-660nm, the wavelength of the green light is 520-560nm, and the wavelength of the blue light is 470-490nm.

4. The low blue light eye-protection head-up display optical system according to any one of claims 1-3, characterized in that, The head-up display body includes a first reflector, a second reflector, a windshield, a virtual image surface, and a human eye. The backlight module is located below the first reflector. The backlight module emits a light source that is projected onto the first reflector. The first reflector reflects the light source onto the second reflector. The second reflector reflects the light source onto the windshield. The light source is reflected by the windshield and enters the human eye. The human eye obtains the virtual image surface through the windshield. The virtual image surface is located on the outside of the windshield.

5. The low blue light eye-protection head-up display optical system according to claim 4, characterized in that, The blue light chips on the light panel are arranged in a 3-row, 4-column layout.

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