TWI884584B - Head-up display device - Google Patents

Abstract

A head-up display device including a projection module and an image light transmission module is provided. The projection module includes an image light source and a projection lens. The image light source is adapted to provide an image beam. The projection lens has a projection lens lateral chromatic aberration. The image light transmission module includes an optical waveguide element and an optical lens element, and has an image light transmission module lateral chromatic aberration. The optical waveguide element is arranged on the transmission path of the image beam from the projection lens and generates the display beam. The projection lens lateral chromatic aberration is reverse chromatic aberration, and the image light transmission module lateral chromatic aberration is forward chromatic aberration.

Description

Heads-up display

The present invention relates to a display device, and in particular to a heads-up display device.

In today's society, in addition to performance, the requirements for transportation vehicles have also begun to focus on the requirements for transportation vehicle interior and safety equipment. The assistance of these technological products (such as in-car voice navigation systems, voice collision warning systems, etc.) has indeed improved the accident rate caused by drivers' fatigue driving for a long time and lack of concentration. But at the same time, non-voice information display devices are usually installed on the instrument panel, and when the driver looks down, it is easy to affect driving safety.

The head-up display (HUD) presents the information required by the driver in front of the driver, so that the driver does not need to be distracted by lowering or turning his head, which can help traffic safety. If the head-up display is installed in the car, when the driver is driving the car, the screen with different traffic information or auxiliary driving functions can be displayed at different positions, so that the driver can obtain corresponding information at different positions of the windshield. However, the head-up display currently using optical waveguides has the problem of lateral chromatic aberration. The so-called lateral chromatic aberration refers to the different wavelengths of light of different colors in the same medium, and the light transmission path (such as refraction) is also different. Due to the different transmission paths of light, different colors of light that should have been transmitted to the same position are transmitted to nearby positions, so the image produces color separation or edge blur. This kind of color aberration is called lateral chromatic aberration. Lateral chromatic aberration is generally more serious at the edge of the picture.

The "prior art" section is only used to help understand the content of the present invention. Therefore, the content disclosed in the "prior art" section may contain some content that does not constitute the common knowledge of the person skilled in the art. The content disclosed in the "prior art" section does not mean that the content or the problem to be solved by one or more embodiments of the present invention has been known or recognized by the person skilled in the art before the application of the present invention.

The present invention provides a head-up display device, which can reduce the lateral chromatic aberration of an image and make the display screen have good optical quality.

Other purposes and advantages of the present invention can be further understood from the technical features disclosed in the present invention.

In order to achieve one or part or all of the above purposes or other purposes, the present invention provides a head-up display device, including a projection module and an image light transmission module. The projection module includes an image light source and a projection lens. The image light source is used to provide an image light beam. The projection lens is arranged on the transmission path of the image light beam. The projection lens has a lateral chromatic aberration of the projection lens. The image light transmission module includes an optical waveguide element and an optical lens, and has a lateral chromatic aberration of the image light transmission module. The optical waveguide element is arranged on the transmission path of the image light beam from the projection lens, and generates a display light beam. The optical lens is arranged on the transmission path of the display light beam from the optical waveguide element. The lateral chromatic aberration of the projection lens is negative chromatic aberration, and the lateral chromatic aberration of the image light transmission module is positive chromatic aberration.

In an embodiment of the present invention, the projection lens comprises at least two first lens elements and at least one second lens element, and the Abbe number of the at least one second lens element is less than 25.

In one embodiment of the present invention, the average Abbe number of the at least two first lens elements is more than twice the average Abbe number of the at least one second lens element.

In an embodiment of the present invention, the number of the at least one second lens element is plural, and there is at least one or at least two first lens elements between adjacent at least one second lens elements.

In an embodiment of the present invention, the lens element of the projection lens is composed of at least two first lens elements and at least one second lens element. The number of the at least two first lens elements is five, and the number of the at least one second lens element is two.

In an embodiment of the present invention, the above-mentioned image light beam forms an image frame having a plurality of image pixels, the image frame has a lateral chromatic aberration of the projection lens, and the width of the lateral chromatic aberration of the projection lens is greater than the width of one or more image pixels.

In one embodiment of the present invention, the display light beam passing through the optical lens forms a display screen, and the display screen has a lateral chromatic aberration of the head-up display device, and the lateral chromatic aberration of the head-up display device is smaller than the lateral chromatic aberration of the projection lens.

In one embodiment of the present invention, the display screen has a plurality of display pixels, and the width of the lateral color difference of the head-up display device is less than the width of one display pixel.

In one embodiment of the present invention, the optical waveguide element comprises a light input area and a light output area, the projection module is disposed corresponding to the light input area, and the optical lens is disposed corresponding to the light output area.

In an embodiment of the present invention, the optical waveguide element comprises a first surface, a second surface and a side surface, wherein the side surface is connected between the first surface and the second surface. The light input area and the light output area are respectively disposed on the first surface and the second surface.

In one embodiment of the present invention, no reflective element is disposed between the optical lens and the light output region.

In one embodiment of the present invention, the optical lens is a free-form surface lens.

In an embodiment of the present invention, the at least one second lens element is a positive lens.

Based on the above, the embodiments of the present invention have at least one of the following advantages or effects. In the head-up display device of the present invention, the head-up display device includes a projection module and an image light transmission module. Among them, the lateral chromatic aberration of the projection lens is a reverse chromatic aberration, and the lateral chromatic aberration of the image light transmission module is a forward chromatic aberration. Therefore, the light beam can have an optical effect of reverse chromatic aberration after passing through the projection lens. In this way, the reverse chromatic aberration generated by the projection lens and the forward chromatic aberration generated by the image light transmission module can be offset by optical design, thereby reducing the degree of lateral chromatic aberration generated by the image light transmission module, so that the display screen of the head-up display device has good optical quality.

In order to make the above features and advantages of the present invention more clearly understood, embodiments are specifically cited below and described in detail with reference to the accompanying drawings.

The above-mentioned other technical contents, features and effects of the present invention will be clearly presented in the detailed description of the preferred embodiment with reference to the following drawings. The directional terms mentioned in the following embodiments, such as up, down, left, right, front or back, etc., are only referenced to the directions of the attached drawings. Therefore, the directional terms used are used to illustrate and are not used to limit the present invention.

FIG1 is a schematic diagram of an application of a head-up display device according to an embodiment of the present invention. Please refer to FIG1. This embodiment provides a head-up display device 100, including a projection module 110 and an image light transmission module 10, wherein the image light transmission module 10 includes an optical waveguide element 120 and an optical lens 130. The projection module 110 provides an image light beam A1 to the optical waveguide element 120 of the image light transmission module 10, and a display light beam A2 is generated through the optical waveguide element 120, and is transmitted to an external imaging element 50 after passing through the optical lens 130. The imaging element 50 reflects the display light beam A2 from the head-up display device 100 to the eyes of a viewer B (for example, a driver of a vehicle), so that the viewer B can see a virtual image with driving information in front of the imaging element 50. The imaging element 50 is, for example, a windshield or a see-through combiner (eg, a semi-transparent element), but the present invention is not limited thereto.

The optical waveguide element 120 is disposed on the transmission path of the image beam A1 from the projection module 110, and generates a display beam A2. The optical waveguide element 120 includes a light input area 121 and a light output area 122. The projection module 110 is disposed corresponding to the light input area 121, and the optical lens 130 is disposed corresponding to the light output area 122. For example, in this embodiment, the optical waveguide element 120 includes a first surface S1, a second surface S2, and a side surface S3, the side surface S3 is connected between the first surface S1 and the second surface S2, and the light input area 121 and the light output area 122 are disposed on the second surface S2. However, in another embodiment, the light input area 121 and the light output area 122 can be disposed on the first surface S1 and the second surface S2, respectively, and the present invention is not limited thereto.

The optical lens 130 is disposed on the transmission path of the display light beam A2 from the optical waveguide element 120. Specifically, in this embodiment, the optical lens 130 includes a free-form surface lens, and the number of lenses of the optical lens 130 is one or more than two, so that the deformation of the image screen can be eliminated. In one embodiment, the optical lens 130 is, for example, a free-form surface lens. In another embodiment, the number of lenses of the optical lens 130 is two, for example, a biconcave lens and a biconvex lens (at least one of which is a free-form surface lens), and they are sequentially disposed on the transmission path of the display light beam A2 from the optical waveguide element 120. In addition, it is worth mentioning that in this embodiment, the head-up display device 100 does not need to be additionally equipped with a reflector, for example, no reflective element is provided between the optical lens 130 and the light output area 122 of the optical waveguide element 120 (on the light transmission path). In other words, compared with a conventional head-up display, the head-up display device 100 of this embodiment has the effect of reducing the size of the device.

FIG. 2 is a schematic diagram of the projection lens in FIG. 1 . Please refer to FIG. 1 and FIG. 2 . The projection module 110 includes an image light source 112 and a projection lens 200. The image light source 112 is used to provide an image light beam A1. In the present embodiment, the image light source 112 includes, for example, an image generating element such as a light source module and/or an optical machine module (not shown), and the image light source 112 is, for example, a projector, but is not limited thereto. The projection lens 200 is disposed on the transmission path of the image light beam A1, and is used to project the image light beam A1 out of the projection module 110 and transmit it toward the optical waveguide element 120.

FIG3 is a diagram showing the lateral chromatic aberration of the projection lens of FIG2. FIG4 is a diagram showing the lateral chromatic aberration of the image light transmission module of the head-up display device of FIG1. The lateral chromatic aberration diagram shown in FIG3 is the lateral chromatic aberration generated when the light beam passes through the projection lens 200 alone, and the lateral chromatic aberration diagram shown in FIG4 is the lateral chromatic aberration generated when the light beam passes through the image light transmission module 10 (i.e., the optical waveguide element 120 and the optical lens 130) alone (it should be noted that the imaging element 50 does not produce the effect of lateral chromatic aberration on the light beam, or the effect is very small). In one embodiment, the image light transmission module 10 is an optical element other than the projection module 110 (projection lens 200) on the optical path of the image beam A1 and the display beam A2 (for example, between the projection lens 200 and the imaging element 50). Please refer to Figures 2 to 4. It is worth mentioning that the projection lens 200 includes at least two first lens elements 210 and at least one second lens element 220, and the Abbe number of each first lens element 210 is greater than or equal to 25, and the Abbe number of the second lens element 220 is less than 25. In a preferred embodiment, the average Abbe number of the first lens element 210 is more than twice the average Abbe number of the second lens element 220. With this design, the light beam can have an optical effect of reverse chromatic aberration only after passing through the projection lens 200. That is, after the light beam passes through the projection lens 200, it has a projection lens lateral chromatic aberration on the image plane (relative to the center of the screen), and the projection lens lateral chromatic aberration is the lateral focus position of the short-wavelength (e.g., blue light) light beam minus the lateral focus position of the long-wavelength (e.g., red light) light beam, which is less than 0 (as shown in FIG. 3, the lateral chromatic aberration is a negative value, i.e., reverse chromatic aberration). After the light beam passes through the image light transmission module 10, it has an image light transmission module lateral chromatic aberration on the image plane, and the image light transmission module lateral chromatic aberration is the lateral focus position of the short-wavelength light beam minus the lateral focus position of the long-wavelength light beam, which is greater than 0 (as shown in FIG. 4, the lateral chromatic aberration is a positive value, i.e., positive chromatic aberration). Specifically, the lateral chromatic aberration of the image light transmission module 10 can be measured by, for example, injecting a light beam without lateral chromatic aberration (or with very small lateral chromatic aberration) into the light input portion of the image light transmission module 10 (e.g., the light input region 121 of the optical waveguide element 120), and measuring the lateral chromatic aberration of the emitted light beam at the light output portion of the image light transmission module 10 (e.g., the surface of the optical lens 130 away from the optical waveguide element 120). Therefore, the chromatic aberration direction of the lateral chromatic aberration of the projection lens is different from the chromatic aberration direction of the lateral chromatic aberration of the image light transmission module, as shown in the difference between FIG. 3 and FIG. 4 .

On the other hand, if the image beam A1 from the projection lens 200 can form an image frame having a plurality of image pixels, then the image frame has a projection lens lateral chromatic aberration (or reverse chromatic aberration), and the projection lens lateral chromatic aberration is, for example, a lateral chromatic aberration at the junction of an edge area of the image frame (for example, the width of the edge area of the image frame is 25% of the width of the image frame) and a central area of the image frame (the image frame area excluding the edge area of the image frame). If the display light beam A2 passing through the optical lens 130 can form a display screen having a plurality of display pixels, then the display screen has a head-up display device lateral chromatic aberration (the definition of head-up display device lateral chromatic aberration is similar to the projection lens lateral chromatic aberration, and the head-up display device lateral chromatic aberration is, for example, the lateral chromatic aberration of the image observed by the viewer B). In this way, the reverse chromatic aberration generated by the projection lens 200 and the forward chromatic aberration generated by the image light transmission module 10 can be offset by optical design, thereby reducing the degree of lateral chromatic aberration generated by the image light transmission module, so that the display screen of the head-up display device 100 has good optical quality. When calculating the lateral chromatic aberration, the width of the lateral chromatic aberration can be defined as the maximum distance between the positions of different visible wavelengths on the optimal focus plane. In a preferred embodiment, the width of the lateral chromatic aberration of the projection lens can be designed to be greater than the width of 10 image pixels. Therefore, by offsetting the lateral chromatic aberration generated by the image light transmission module 10 through the above design, the lateral chromatic aberration of the head-up display device will be smaller than the lateral chromatic aberration of the projection lens, so that the width of the lateral chromatic aberration of the head-up display device is less than the width of 1 display pixel, thereby achieving the effect of reducing the lateral chromatic aberration.

Please continue to refer to FIG. 2. Based on the above principle, this embodiment provides an embodiment as described below. The number of at least one second lens element 220 of the projection lens 200 is plural, and there is at least one first lens element 210 between adjacent second lens elements 220. For example, in this embodiment, the projection lens 200 includes an aperture ST, a first lens L1, a second lens L2, a third lens L3, a fourth lens L4, a fifth lens L5, a sixth lens L6, a seventh lens L7, a prism 230, a filter 240 and an imaging surface S99 in sequence from the object side D1 to the image side D2 along the optical axis C. The first lens element 210 includes a first lens L1, a third lens L3, a fourth lens L4, a fifth lens L5 and a sixth lens L6, and the second lens element 220 includes a second lens L2 and a seventh lens L7. In other words, the lens element of the projection lens head 200 is composed of a first lens element 210 and a second lens element 220, the number of the first lens elements 210 is 5, and the number of the second lens elements 220 is 2.

Specifically, in this embodiment, the first lens L1 is a concave-convex lens with the convex surface facing the aperture ST. In addition, the fifth lens L5 and the sixth lens L6 are double laminated lenses, the absolute value of the focal length of the double laminated lens is greater than 35, and the absolute value of the difference in Abbe number is greater than 50. With the above conditions, the projection lens 200 of this embodiment has a better reverse chromatic aberration effect. In this embodiment, the lateral reverse chromatic aberration generated by the projection lens 200 is greater than the width of 10 image pixels. The actual design of each component of the projection lens 200 can be seen in the following Table 1. In Table 1, the optical elements from the aperture ST to the imaging surface S99 have object side surfaces S11, S21, S31, S41, S51, S61, S71, S81, S91 and image side surfaces S12, S22, S32, S42, S62, S72, S82, S92 from the object side D1 to the image side D2. Table 1 element surface Radius of curvature (mm) Abbe number (Vd) ST infinite L1 S11 21.8 49.6 S12 29.8 L2 S21 41.1 17.5 S22 83.4 L3 S31 27.3 49.6 S32 159.3 L4 S41 878.9 29.5 S42 12.0 L5 S51 13.1 81.5 L6 S61 -21.8 25.4 S62 16.7 L7 S71 26.6 18.9 S72 -471.8 230 S81 infinite 56.7 S82 infinite 240 S91 infinite 64.2 S92 infinite S99 infinite

As can be seen from Table 1 above, in this embodiment, the average Abbe number 47.12 of the first lens element 210 (i.e., the first lens L1, the third lens L3, the fourth lens L4, the fifth lens L5, and the sixth lens L6) is more than twice the average Abbe number 18.2 of the second lens element 220 (i.e., the second lens L2 and the seventh lens L7). In an embodiment where the second lens element 220 has only one lens, the second lens element 220 can be selectively disposed at an end closer to the image light source 112. In another embodiment, the number of lenses of the second lens element 220 may be three or more, the number of lenses of the first lens element 210 may also be greater than five, and there is at least one first lens element 210 between adjacent second lens elements 220. It is particularly noted that no matter the number of the second lens elements 220 is one, two, or more than two, at least one second lens element 220 is a positive lens (with a positive refractive index).

FIG5 is a modulation transfer function diagram of the projection lens of FIG2. Please refer to FIG5. FIG5 is a modulation transfer function (MTF) diagram of the projection lens 200 at different image heights, wherein the horizontal axis is the focus shift and the vertical axis is the modulus of the optical transfer function. It can be verified that the optical transfer function curve displayed by the projection lens 200 of this embodiment is within the standard range, so it has good optical imaging quality, as shown in FIG5.

FIG6 is a diagram of field curvature aberration of the projection lens of FIG2. FIG7 is a diagram of distortion aberration of the projection lens of FIG2. Please refer to FIG6 and FIG7. FIG6 is a diagram of field curvature aberration in the sagittal direction and field curvature aberration in the tangential direction of the projection lens 200 of FIG2 on the imaging surface. The focal length variation of the main visible wavelength in the entire field of view falls within ±0.02 mm, indicating that the projection lens 200 of this embodiment can effectively eliminate aberrations. FIG. 7 illustrates the distortion aberration of the projection lens 200 of FIG. 2 on the imaging surface. The distortion aberration diagram of FIG. 7 shows that the distortion aberration of the projection lens 200 of this embodiment can be maintained within a range of ±1.0%, indicating that the distortion aberration of this embodiment meets the general imaging quality requirements.

In summary, the head-up display device of the embodiment of the present invention has at least one of the following advantages: In the head-up display device of the present invention, the head-up display device includes a projection module, an optical waveguide element and an optical lens. Among them, the projection module includes an image light source and a projection lens. The projection lens includes at least two first lens elements and at least one second lens element, and the Abbe number of the second lens element is less than 25. Therefore, the light beam can have an optical effect of reverse chromatic aberration after passing through the projection lens. In this way, the reverse chromatic aberration generated by the projection lens and the forward chromatic aberration generated by the image light transmission module can be offset by optical design, thereby reducing the degree of lateral chromatic aberration generated by the image light transmission module, so that the display screen of the head-up display device has good optical quality.

However, the above is only the preferred embodiment of the present invention, and it cannot be used to limit the scope of the implementation of the present invention. That is, all simple equivalent changes and modifications made according to the scope of the patent application and the content of the invention description are still within the scope of the present invention. In addition, any embodiment or patent application of the present invention does not need to achieve all the purposes, advantages or features disclosed by the present invention. In addition, the abstract and title are only used to assist in searching for patent documents, and are not used to limit the scope of rights of the present invention. In addition, the terms "first", "second", etc. mentioned in this specification or patent application are only used to name the element or distinguish different embodiments or scopes, and are not used to limit the upper or lower limit of the number of elements.

10: Image light transmission module 50: Imaging element 100: Head-up display device 110: Projection module 112: Image light source 120: Optical waveguide element 121: Light input area 122: Light output area 130: Optical lens 200: Projection lens 210: First lens element 220: Second lens element 230: Prism 240: Filter A1: Image beam A2: Display beam B: Observer C: Optical axis D1: Object side D2: Image side L1: First lens L2: Second lens L3: Third lens L4: Fourth lens L5: Fifth lens L6: Sixth lens L7: seventh lens S1: first surface S2: second surface S3: side surface S11, S21, S31, S41, S51, S61, S71, S81, S91: object side surface S12, S22, S32, S42, S62, S72, S82, S92: image side surface S99: imaging surface ST: aperture

FIG1 is a schematic diagram of an application of a head-up display device of an embodiment of the present invention. FIG2 is a schematic diagram of a projection lens in FIG1. FIG3 is a schematic diagram of lateral chromatic aberration of the projection lens in FIG2. FIG4 is a schematic diagram of lateral chromatic aberration of an image light transmission module of the head-up display device in FIG1. FIG5 is a modulation transfer function diagram of the projection lens in FIG2. FIG6 is a field curvature aberration diagram of the projection lens in FIG2. FIG7 is a distortion aberration diagram of the projection lens in FIG2.

10: Image light transmission module 50: Imaging element 100: Head-up display device 110: Projection module 112: Image light source 120: Optical waveguide element 121: Light input area 122: Light output area 130: Optical lens 200: Projection lens A1: Image beam A2: Display beam B: Observer S1: First surface S2: Second surface S3: Side surface

Claims (15)

A head-up display device is used to provide a display beam to an imaging element, the head-up display device comprising: A projection module, comprising an image light source and a projection lens, the image light source is used to provide an image beam, the projection lens is arranged on the transmission path of the image beam, the projection lens has a projection lens lateral chromatic aberration; and An image light transmission module, having an image light transmission module lateral chromatic aberration, the image light transmission module comprising: An optical waveguide element, arranged on the transmission path of the image beam from the projection lens, and generating the display beam; and An optical lens is arranged on the transmission path of the display light beam from the optical waveguide element, wherein the lateral chromatic aberration of the projection lens is a reverse chromatic aberration, and the lateral chromatic aberration of the image light transmission module is a forward chromatic aberration; wherein the display light beam is transmitted to the imaging element after passing through the optical lens. A heads-up display device as described in claim 1, wherein the projection lens includes at least two first lens elements and at least one second lens element, and the Abbe number of the at least one second lens element is less than 25. A head-up display device as described in claim 2, wherein the average Abbe number of the at least two first lens elements is more than twice the average Abbe number of the at least one second lens element. A heads-up display device as described in claim 2, wherein the number of the at least one second lens element is plural, and there is at least one of the at least two first lens elements between adjacent at least one second lens elements. A head-up display device as described in claim 2, wherein the lens element of the projection lens is composed of at least two first lens elements and at least one second lens element, the number of the at least two first lens elements is 5, and the number of the at least one second lens elements is 2. A head-up display device as described in claim 1, wherein the image light beam forms an image screen having a plurality of image pixels, the image screen has the lateral chromatic aberration of the projection lens, and the width of the lateral chromatic aberration of the projection lens is greater than the width of one of the plurality of image pixels. A head-up display device as described in claim 6, wherein the display light beam passing through the optical lens forms a display screen, and the display screen has a lateral chromatic aberration of the head-up display device, and the lateral chromatic aberration of the head-up display device is smaller than the lateral chromatic aberration of the projection lens. A head-up display device as described in claim 7, wherein the display screen has multiple display pixels, and the width of the lateral color difference of the head-up display device is less than the width of one of the multiple display pixels. A heads-up display device as described in claim 1, wherein the optical waveguide element includes a light input area and a light output area, the projection module is arranged corresponding to the light input area, and the optical lens is arranged corresponding to the light output area. A head-up display device as described in claim 9, wherein the optical waveguide element includes a first surface, a second surface and a side surface, the side surface is connected between the first surface and the second surface, and the light input area and the light output area are respectively arranged on the first surface and the second surface. A head-up display device as described in claim 9, wherein no reflective element is provided between the optical lens and the light output area. A heads-up display device as described in claim 1, wherein the optical lens is a free-form lens. A head-up display device as described in claim 2, wherein the at least one second lens element is a positive lens. A head-up display device comprises: A projection module, comprising an image light source and a projection lens, wherein the image light source is used to provide an image beam, the projection lens is arranged on the transmission path of the image beam, and the projection lens has a projection lens lateral chromatic aberration; and An image light transmission module, having an image light transmission module lateral chromatic aberration, the image light transmission module comprising: An optical waveguide element, arranged on the transmission path of the image beam from the projection lens, and generating a display beam; and An optical lens, arranged on the transmission path of the display beam from the optical waveguide element, wherein the projection lens lateral chromatic aberration is a reverse chromatic aberration, and the image light transmission module lateral chromatic aberration is a forward chromatic aberration; The projection lens includes at least two first lens elements and at least one second lens element, and the Abbe number of the at least one second lens element is less than 25. A head-up display device comprises: A projection module, comprising an image light source and a projection lens, wherein the image light source is used to provide an image beam, the projection lens is arranged on the transmission path of the image beam, and the projection lens has a projection lens lateral chromatic aberration; and An image light transmission module, having an image light transmission module lateral chromatic aberration, the image light transmission module comprising: An optical waveguide element, arranged on the transmission path of the image beam from the projection lens, and generating a display beam; and An optical lens, arranged on the transmission path of the display beam from the optical waveguide element, wherein the projection lens lateral chromatic aberration is a reverse chromatic aberration, and the image light transmission module lateral chromatic aberration is a forward chromatic aberration; The image beam forms an image frame having a plurality of image pixels, the image frame has the lateral chromatic aberration of the projection lens, and the width of the lateral chromatic aberration of the projection lens is greater than the width of one of the plurality of image pixels.

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