Mirror unit and head-up display device

Abstract

The utility model provides a reflecting mirror unit and a head-up display device, and the reflecting mirror unit (30) is provided with a main body plate part (31) which is roughly in a rectangular plate shape and is made of synthetic resin; a reflective layer (32) that is formed on one surface of the main body plate section (31) and reflects the display light; two shaft sections (33L, 33R) provided at the ends of both sides in the X direction; and ribs (35a-35d) which are vertically arranged on the other back surface (31B) of the main body plate part (31) and extend along the rib extension direction (V). The width of the ribs (35a-35d) in the direction orthogonal to the rib extension direction (V) is formed so as to be 50% or more of the thickness of the main body plate section (31). According to the reflector unit and the head-up display device provided by the utility model, the intensity can be further improved through a simple structure, and the reduction of image quality can be inhibited.

Description

Technical Field

[0001] This utility model relates to a reflector unit and a head-up display device. Background Technology

[0002] The head-up display device described in Patent Document 1 includes a reflector unit that reflects display light from the display unit onto the windshield. This reflector unit includes a concave mirror and a bracket that supports the concave mirror from the back. The bracket is formed of synthetic resin in a rectangular plate shape, and multiple ribs for increased strength are formed on the back of the bracket (see paragraph 0022 of Patent Document 1). Figure 7 ).

[0003] The concave mirror of the head-up display device described in Patent Document 2 is formed by vapor-depositing metal (e.g., aluminum) onto resin to create a reflective surface (see paragraph 0015 of Patent Document 2).

[0004] The positioning structure described in Patent Document 3 includes a positioning pin consisting of ribs extending from the center in three or four directions. Furthermore, Patent Document 3 discloses that if the width of the rib is less than 50% of the thickness of the outer surface, shrinkage marks will not occur on the outer surface (see paragraph 0015 of Patent Document 3).

[0005] Existing technical documents

[0006] Patent documents

[0007] Patent Document 1: International Publication No. 2019 / 124331

[0008] Patent Document 2: Japanese Patent Application Publication No. 2021-154929

[0009] Patent Document 3: Japanese Patent Application Publication No. 2005-277349 Utility Model Content

[0010] Technical problem to be solved by the utility model

[0011] In the structure described in Patent Document 1, the concave mirror and the support are manufactured separately, and the concave mirror is bonded to the bonding surface of the support. However, the concave mirror and the support need to be constructed separately, and the structure is not simple.

[0012] In the structure of vapor-depositing a reflective surface on a support described in Patent Document 2, the structure is simple. However, in this structure, if the width of the ribs is increased to improve strength when ribs are provided, shrinkage marks will occur, which may reduce the shape accuracy of the reflective surface and the image quality of the projected image based on the reflected display light.

[0013] This invention was made in view of the above-mentioned actual situation, and its purpose is to provide a mirror unit and head-up display device that can further improve strength with a simple structure while suppressing the reduction of image quality.

[0014] Technical solutions adopted to solve technical problems

[0015] To achieve the above objectives, the reflector unit according to the first aspect of this utility model comprises: a generally rectangular plate-shaped main body plate portion formed of synthetic resin; a reflective layer formed on one surface of the main body plate portion for reflecting and displaying light; two shaft portions disposed at the ends of both sides in the long side direction of the main body plate portion; and a rib disposed vertically on the other surface of the main body plate portion, extending along the rib extension direction, wherein the width of the rib in a direction orthogonal to the rib extension direction is formed to a length of at least 50% of the thickness of the main body plate portion.

[0016] To achieve the above objectives, the head-up display device according to the second aspect of this utility model comprises: a display device that radiates display light; a reflector unit that reflects the display light; and a reflector drive mechanism that rotates the reflector unit about a rotation axis that passes through the two shaft portions and is inclined relative to the long side direction.

[0017] Utility Model Effect

[0018] According to this invention, strength can be further improved with a simple structure while suppressing the reduction in image quality. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a vehicle equipped with a head-up display device according to one embodiment of the present invention.

[0020] Figure 2 This is a schematic diagram illustrating the structure of a head-up display device according to one embodiment of the present invention.

[0021] Figure 3 This is a perspective view of a reflector unit according to one embodiment of the present invention.

[0022] Figure 4 This is a perspective view of a reflector unit according to one embodiment of the present invention.

[0023] Figure 5 This is a top view of a reflector unit according to one embodiment of the present invention.

[0024] Figure 6 This is a rear view of a reflector unit according to one embodiment of the present invention.

[0025] Figure 7 yes Figure 4 A cross-sectional view of line VII-VII.

[0026] Figure 8 This is a perspective view of the reflector unit involved in a modified example of this utility model. Detailed Implementation

[0027] The reflector unit and head-up display device according to one embodiment of the present invention will be described with reference to the accompanying drawings.

[0028] like Figure 1 As shown, a head-up display (HUD) 100 is installed inside the dashboard of a vehicle 200. The HUD 100 emits display light L representing an image toward the windshield 201, which is an example of a projection component of the vehicle 200. The display light L is reflected by the windshield 201 and reaches a visual observer 1 (primarily the driver of the vehicle 200). Thus, the HUD 100 displays a virtual image Q in a manner that overlaps with the real scene seen through the windshield 201.

[0029] like Figure 2 As shown, the head-up display device 100 includes a display device 10, a folding mirror 20, a mirror unit 30, a mirror drive mechanism 50, and a frame 60.

[0030] The frame 60 is made of opaque resin or metal and is a hollow, roughly rectangular prism. The reflecting mirror 20, the reflecting mirror unit 30, and the reflecting mirror drive mechanism 50 are housed within the frame 60.

[0031] The frame 60 has an opening 61a opposite to the windshield 201. The frame 60 has a curved, plate-shaped window 65 that seals the opening 61a. The window 65 is made of a light-transmitting resin material such as acrylic that allows light L to pass through.

[0032] The display device 10 emits display light L under the control of a control unit (not shown). The display device 10 includes a TFT (Thin Film Transistor) liquid crystal display panel 11 and a backlight 12 for illuminating the display panel 11.

[0033] Furthermore, the display device 10 may be of the type that includes a display panel 11, but is not limited thereto; it may be of any type as long as it can emit display light L. For example, the display device 10 may be of the type that includes an OLED (Organic Light-Emitting Diode), or a type that receives reflected light formed by a DMD (Digital Micromirror Device) and displays an image on a transmissive screen.

[0034] The retroreflector 20 is a correction mirror that reflects the display light L from the display device 10 toward the reflector unit 30. The reflective surface 20a of the retroreflector 20 has a convex curved surface in the width direction and a concave curved surface in the height direction. The reflective surface 20a has a curvature (the reciprocal of the radius of curvature) that causes the reflected display light L to cross vertically at the intersection point CP before reaching the reflector unit 30.

[0035] Furthermore, the reflecting mirror 20 is not limited to curved mirrors; it can also be a plane mirror.

[0036] The reflector unit 30 is a concave mirror unit that amplifies and reflects the display light L reflected by the folding mirror 20 toward the windshield 201. The specific structure of the reflector unit 30 will be described later.

[0037] The reflector drive mechanism 50 is configured to rotate the reflector unit 30 about a rotation axis J extending along the vehicle width direction. By rotating the reflector unit 30 about the rotation axis J, the illumination position of the display light L relative to the visual observer 1 is adjusted in the height direction.

[0038] like Figures 3-6 As shown, the reflector unit 30 includes a main body plate 31, a reflective layer 32, shaft portions 33L and 33R, ribs 35a to 35d, connecting portions 37 and 38, and a plate portion 36.

[0039] In the following description, the long side direction of the reflector unit 30 is the X direction, the short side direction is the Y direction, and the thickness direction is the Z direction. The X direction is the direction corresponding to the left-right direction of the virtual image Q when viewed by visual observer 1, i.e., the vehicle width direction; the Y direction is the direction corresponding to the up-down direction of the virtual image Q when viewed by visual observer 1; and the Z direction is the direction corresponding to the depth direction of the virtual image Q when viewed by visual observer 1.

[0040] In the following description, left and right are defined as the directions when viewing the reflecting surface of the reflector unit 30 from the front.

[0041] The main body plate 31, shaft portions 33L and 33R, and ribs 35a to 35d are integrally molded from synthetic resin as synthetic resin parts. Alternatively, the shaft portion 33L can also be separately constructed from the main body plate 31, shaft portion 33R, and ribs 35a to 35d.

[0042] The main body plate 31 is a generally rectangular plate that is longer in the X direction and shorter in the Y direction. The main body plate 31 is curved into a concave shape in both the X and Y directions.

[0043] The upper and lower sides of the main body plate 31 extend parallel to the X direction.

[0044] A reflective layer 32 is formed on the surface of the main body plate 31 (the surface on the side of the reflective mirror 20). The reflective layer 32 is formed on the surface of the main body plate 31, for example, by vapor deposition of a metal such as aluminum.

[0045] Shaft portions 33L and 33R are located at both ends of the main body plate portion 31 in the X direction.

[0046] The shaft portion 33R is located on the right side of the main body plate portion 31 and is generally cylindrical, extending in the X direction. The shaft portion 33R is located slightly above the center of the right side of the main body plate portion 31 in the Y direction. The shaft portion 33R is housed in a recess (not shown) within the frame 60. In this housed state, a leaf spring (not shown) applies force to the shaft portion 33R, thereby supporting the shaft portion 33R in a rotatable manner within the frame 60.

[0047] The shaft portion 33L is located on the left side of the main body plate portion 31 and is rectangular in shape. The shaft portion 33L is positioned slightly below the center in the Y direction on the right side of the main body plate portion 31. The shaft portion 33L is equipped with... Figure 3 The receiving component 39 is shown by a single-dotted line. The receiving component 39 receives the driving force from the mirror drive mechanism 50, thereby causing the mirror unit 30 to rotate about the rotation axis J.

[0048] The rotation axis J of the reflector unit 30 is tilted relative to the X direction. The tilt angle θ of the rotation axis J relative to the X direction (refer to...) Figure 6 The angle is set to 2° to 5°, preferably about 3.5°.

[0049] Ribs 35a to 35d are erected on the back side 31B of the main body plate 31 (the side opposite to the reflective layer 32).

[0050] Ribs 35a to 35d extend in the rib extension direction V. Ribs 35a to 35d are formed such that they traverse the entire area of ​​the back surface 31B of the main body plate portion 31 in the X direction. Ribs 35a to 35d extend parallel to each other. The rib extension direction V extends in the direction of the rotation axis J and is inclined relative to the X direction (the direction in which the upper and lower side surfaces of the main body plate portion 31 extend). The inclination angle α of the rib extension direction V relative to the X direction (refer to...) Figure 6 The angle is set to 2° to 5°, preferably about 3.5°.

[0051] Ribs 35b and 35c are arranged such that they clamp the rotation axis J in the Y direction. Ribs 35a and 35d are arranged such that they clamp ribs 35b and 35c in the Y direction.

[0052] Ribs 35b and 35c have inclined portions 35b1 and 35c1 located at their ends on the side of the shaft portion 33L in the rib extension direction V. The inclined portions 35b1 and 35c1 are inclined such that they approach the rotation axis J as they approach the shaft portion 33L. The outer ends of the inclined portions 35b1 and 35c1 in the rib extension direction V are connected to a connecting portion 37. The connecting portion 37 is located at the end of the back surface 31B on the side of the shaft portion 33L and is a cuboid extending in the Y direction.

[0053] Furthermore, ribs 35b and 35c may not have an inclined portion and may be formed in a straight line along the entire length of the rotation axis J. However, in order to avoid the position where the ejector pin abuts, they may also have such an inclined portion 35b1 and 35c1.

[0054] Ribs 35b and 35c have inclined portions 35b2 and 35c2 located at their ends on the shaft portion 33R side in the rib extension direction V. The inclined portions 35b2 and 35c2 are inclined such that they move away from the rotation axis J as they approach the shaft portion 33R. The outer ends of the inclined portions 35b2 and 35c2 in the X direction are connected to a connecting portion 38. The connecting portion 38 is located at the end of the back surface 31B on the shaft portion 33R side and is a cuboid extending in the Y direction. The connecting portion 38 is formed on both sides of the root of the shaft portion 33R in the Y direction.

[0055] Furthermore, in this respect, ribs 35b and 35c may not have an inclined portion and may be formed in a straight line along the entire length of the rotation axis J. However, in order to avoid the position where the ejector pin abuts, such an inclined portion 35b2 and 35c2 may also be provided.

[0056] Recesses 35b3 and 35c3 are formed at the center of the rib extension direction V on the opposing surfaces of ribs 35b and 35c. The width of the recesses 35b3 and 35c3 increases in the rib extension direction V as they face towards the opposing sides. Recesses 35b3 and 35c3 are where ejector pins (not shown) are inserted during injection molding. Furthermore, it is preferable that the ejector pins are positioned where they do not interfere with the ribs. Additionally, where it is possible to position the ejector pins where they do not interfere with the ribs, it is preferable that ribs 35b and 35c are formed in a straight line along the entire length of the rotation axis J.

[0057] like Figure 7 As shown, the width W of rib 35c is formed with a length that is at least 50% of the thickness Th of the main body plate portion 31. The width W of rib 35c is its length in a direction orthogonal to the rib extension direction V.

[0058] The width W of rib 35c refers to the width of the root of rib 35c.

[0059] The width W of rib 35c is set to 2mm to 6mm, preferably 3.0mm to 4.5mm, and more preferably about 3.8mm.

[0060] The plate thickness Th is set to 2mm to 6mm, preferably 3.0mm to 4.5mm, and more preferably about 3.8mm.

[0061] If the ratio of width W to plate thickness Th is too small, the strength of the reflector unit 30 will be low, resulting in a lower resonance frequency and easy vibration. If the ratio is too large, shrinkage marks may be generated on the surface of the main plate 31.

[0062] From this perspective, the width W of rib 35c is set to 50% to 150% of the thickness Th of the main body plate portion 31, preferably 80% to 120%, more preferably 90% to 110%, and even more preferably about 100%. As an example, both the width W and the thickness Th are set to about 3.8 mm.

[0063] The width W of ribs 35a, 35b, and 35d other than rib 35c is set in the same way as the width W of rib 35c.

[0064] The heights of ribs 35a and 35d, which are based on the back surface 31B, are set to be higher than the heights of ribs 35b and 35c, which are based on the back surface 31B.

[0065] Furthermore, not limited to this example, the heights of each rib from 35a to 35d can also be the same.

[0066] The plate portion 36 is erected on the back surface 31B and is plate-shaped, extending along the rotation axis J. The thickness of the plate portion 36 is made smaller than the width W of each rib 35a to 35d.

[0067] Ribs 35a to 35d and plate portion 36 are arranged at equal intervals in the Y direction.

[0068] As described in Patent Document 3, when ribs are formed in a typical injection molded article, if the ribs are not less than 50% of the thickness of the injection molded article, shrinkage marks will occur on the surface of the injection molded article (the side opposite to the ribs) during the normal cooling time.

[0069] Regarding this, a relatively long cooling time is spent during the injection molding of the synthetic resin part of the reflector unit 30. Therefore, even if wide ribs 35a to 35d with a thickness ratio of 50% or more are formed to improve the strength of the reflector unit 30, shrinkage marks will not occur on the surface of the main body plate portion 31. In other words, the cooling time is set to a time during which shrinkage marks will not occur on the surface of the main body plate portion 31.

[0070] Therefore, the strength of the mirror unit 30 is increased without special manufacturing considerations. By increasing the strength of the mirror unit 30, the resonant frequency of the mirror unit 30 can be increased, and the vibration of the mirror unit 30 can be suppressed.

[0071] (Effect)

[0072] According to one implementation method described above, the following effects are achieved.

[0073] (1) The reflector unit 30 includes: a generally rectangular plate-shaped main body plate 31 formed of synthetic resin; a reflective layer 32 formed on one surface of the main body plate 31, which reflects the display light L; two shaft portions 33L and 33R provided at the ends of both sides in the long side direction (X direction) of the main body plate 31; and ribs 35a to 35d, which are erected on the other back surface 31B of the main body plate 31 and extend along the rib extension direction V. The width W of the ribs 35a to 35d in the direction orthogonal to the rib extension direction V is formed to a length of more than 50% of the thickness (plate thickness Th) of the main body plate 31.

[0074] According to this structure, since a reflective layer 32 is formed on the main body plate 31, the strength of the reflective mirror unit 30 is improved with a simple structure and wide ribs 35a to 35d are formed, while no shrinkage is generated as described above. Therefore, it is possible to suppress the reduction of image quality of the projected image based on the display light L reflected by the reflective mirror unit 30.

[0075] (2) The reflector unit 30 is configured to rotate about a rotation axis J that passes through the two shafts 33L and 33R and is inclined relative to the X direction. Ribs 35a to 35d are formed along the direction of the rotation axis J.

[0076] According to this structure, the strength of the mirror unit 30 is improved by forming ribs 35a to 35d along the direction of the rotation axis J.

[0077] (3) The head-up display device 100 includes a display device 10 that radiates display light L, a reflector unit 30 that reflects display light L, and a reflector drive mechanism 50 that rotates the reflector unit 30 about the rotation axis J.

[0078] According to this structure, it is possible to suppress the degradation of the quality of the projected image (virtual image Q) displayed in the head-up display device 100.

[0079] (Example of variation)

[0080] Furthermore, the above-described embodiments can be implemented in the following manner with appropriate modifications.

[0081] In the above embodiments, the position or shape of the shaft portions 33L and 33R can be changed. The shaft portions 33L and 33R can also be omitted.

[0082] In the above embodiments, the reflector drive mechanism 50 may also be omitted.

[0083] In the above embodiment, the plate portion 36 may be formed as a rib or may be omitted.

[0084] In the above embodiments, the rotation axis J can also extend along the X direction.

[0085] In the above embodiment, the head-up display device 100 is mounted on the vehicle 200, but it can also be mounted on other vehicles such as airplanes and ships. Furthermore, the projected component is not limited to the windshield; it can also be a dedicated assembly.

[0086] In the above embodiments, the reflector unit 30 is a concave mirror unit, but it can also be a plane mirror unit or a freeform mirror unit.

[0087] In the above embodiments, the number, position, shape, or width W of ribs 35a to 35d can be appropriately varied. Ribs 35a to 35d can also extend along the X direction. In this case, the rib extension direction V is the same as the X direction. Ribs 35a to 35d can also extend along the Y direction on the back surface 31B.

[0088] Ribs 35a to 35d can also be formed in a curved shape.

[0089] Moreover, for example, the number of ribs 35a to 35d can be 1 to 3 or more.

[0090] like Figure 8 As shown, the mirror unit 130 has five ribs 135a to 135e, each of which extends along the rib extension direction V and is formed such that the two ends of the rib extension direction V converge at the side of the rotation axis J.

[0091] Rib 135e extends on the rotation axis J.

[0092] Ribs 135b and 135c are arranged such that they sandwich rib 135e in the Y direction, and extend in a straight line along the rib extension direction V over the entire area of ​​the back surface 31B.

[0093] Ribs 135a and 135d are arranged such that ribs 135b and 135c are sandwiched in the Y direction. Ribs 135a and 135d have inclined portions 136a and 136d at both ends located in the rib extension direction V. The inclined portions 136a and 136d are inclined toward the rotation axis J as they approach the two outer sides of the rib extension direction V.

[0094] Explanation of reference numerals in the attached figures

[0095] 1…Visual observer; 10…Display device; 11…Display panel; 12…Backlight; 20…Reflecting mirror; 20a…Reflecting surface; 30, 130…Reflecting mirror unit; 31…Main body plate; 31B…Back side; 32…Reflective layer; 33L, 33R…Shaft; 35a~35d, 135a~135e…Ribs; 35b1, 35c1, 35b2, 35c2, 136a, 136d…Inclined portion; 35b3, 35c3…recess; 36…plate; 37, 38…connecting part; 39…receiving component; 50…mirror drive mechanism; 60…frame; 61a…opening; 65…window; 100…head-up display; 200…vehicle; 201…windshield; J…rotation axis; L…display light; V…rib extension direction; Q…virtual image; CP…intersection point; Th…plate thickness; W…width; θ, α…tilt angle.

Claims

1. A reflector unit, characterized in that, have: The main body plate is roughly rectangular and plate-shaped, and is formed of synthetic resin; A reflective layer, formed on one surface of the main body plate, reflects display light; Two shaft portions are disposed at the ends of both sides of the main body plate in the longitudinal direction; and The rib is erected on the other side of the main body plate and extends along the rib extension direction. The width of the rib in a direction orthogonal to the rib's extension direction is formed with a length that is at least 50% of the thickness of the main body plate.

2. The reflector unit according to claim 1, characterized in that, The mirror unit is configured to rotate about a rotation axis that passes through the two shafts and is inclined relative to the long side. The ribs are formed along the direction of the axis of rotation.

3. A head-up display device, characterized in that, have: A display device that emits display light; The reflector unit according to claim 1 or 2 that reflects the display light; and A mirror drive mechanism that causes the mirror unit to rotate about a rotation axis that passes through the two shafts and is inclined relative to the long side.

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