Optical member, illumination device, and image projection device

Abstract

The invention provides an optical component, an illumination device and an image projection device, which can uniformly irradiate irradiation light on a limited display area and improve the utilization efficiency of the irradiation light. An optical member (100) is provided with a reflecting part (10) having a reflecting surface (12) formed on the inner surface thereof, a light entrance port (17) open at one end of the reflecting surface (12), and a light exit port (16) open at the other end of the reflecting surface (12), and a lens part (20) disposed at the light exit port (16) of the reflecting part (10). The lens part (20) is located in a central region (21) disposed in the center and in a peripheral region (22) provided around the central region (21), and the refractive power of the central region (21) is greater than that of the peripheral region (22).

Description

Technical Field

[0001] The present invention relates to an optical component, a lighting device, and an image projection device. Background Art

[0002] Conventionally, a dashboard that lights up and displays icons has been used as a device for displaying various information inside a vehicle. In addition, it has been proposed to embed an image display device in the dashboard or to form the entire dashboard with an image display device as the amount of information to be displayed increases.

[0003] However, since the dashboard is located below the front windshield (windshield) of the vehicle, in order for a driver or other occupant to identify the information displayed on the dashboard, it is necessary to move the line of sight downward during driving, which is not preferable. Therefore, an image projection device such as a head-up display (hereinafter referred to as HUD: Head Up Display) that projects an image on the front windshield and allows an occupant to read information while looking ahead at the front of the vehicle has been proposed (for example, refer to Patent Documents 1 and 2).

[0004] Regarding the image projection devices of Patent Documents 1 and 2, an image display unit irradiates illumination light including an image, and the illumination light is reflected by a free-form surface mirror or the like so as to reach the position of the occupant's viewing point in such a manner that the image is formed in space via a display unit such as a windshield. Thus, the occupant can use the illumination light incident on the viewing point to recognize the image displayed at the imaging position in the depth direction.

[0005] Prior Art Documents

[0006] Patent Documents

[0007] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2019-119248

[0008] Patent Document 2: Japanese Unexamined Patent Application Publication No. 2019-119262 Summary of the Invention

[0009] Technical Problem to be Solved by the Invention

[0010] In existing image projection devices, a liquid crystal display device or the like is used as an image display unit to display a projection image, and illumination light is irradiated onto the image display area (irradiation area) of the image in the image display unit to project image light. Generally, in an in-vehicle image projection device, in order to present necessary information without obstructing the view, the size of the display area is limited, particularly the size in the height direction, so that the display area is long in the horizontal direction. Therefore, it is required that the lighting device of the image projection device uniformly irradiate the entire area of such a horizontally long display area.

[0011] However, if the irradiation light from the lighting device is to be homogenized laterally, the optical path also expands in the height direction, resulting in an increase in the amount of light reaching outside the display area and a decrease in the utilization efficiency of the light emitted from the light source. In particular, when arranging a plurality of light-emitting elements such as light-emitting diodes (LEDs: Light Emitting Diodes) as the light source of the lighting device, it is difficult to balance the uniform irradiation of light between the plurality of LEDs and the improvement of the utilization efficiency of light in the height direction.

[0012] Therefore, the present invention is proposed in view of the above-mentioned existing problems, and its object is to provide an optical component, a lighting device, and an image projection device that can uniformly irradiate the irradiation light on a limited display area and improve the utilization efficiency of the irradiation light.

[0013] Technical solutions for solving technical problems

[0014] To solve the above technical problems, the present invention provides an optical component, which is characterized by comprising: a reflection part, on the inner surface of which a reflection surface is formed, having a light incident port opening at one end of the reflection surface and a light exit port opening at the other end of the reflection surface; a lens part, which is arranged at the light exit port of the reflection part, and the lens part has a central area located in the center and a peripheral area arranged around the central area, and the optical power of the central area is greater than that of the peripheral area.

[0015] In the optical component of the present invention like this, the lens part is arranged at the light exit port of the reflection part, and the optical power of the central area of the lens part is greater than that of the peripheral area. Therefore, it is possible to separately set the area irradiated by the light directly incident from the light source to the central area and the peripheral area, and the area irradiated by the light reflected by the reflection part and incident on the peripheral area. Thereby, it is possible to uniformly irradiate the irradiation light on a limited display area and improve the utilization efficiency of the irradiation light.

[0016] In addition, in one aspect of the present invention, the distance D between the light exit port and the central area and the width W of the light exit port out satisfy the relationship of D ≤ 0.5W out

[0017] In addition, in one aspect of the present invention, the central area has a convex lens shape in which the light incident surface protrudes in the direction of the reflection part.

[0018] In addition, in one aspect of the present invention, at least a part of the light incident surface is inserted on the light incident port side with respect to the light exit port.

[0019] In addition, in one aspect of the present invention, the width W of the central area c and the width W of the light exit port out satisfy 0.3W​out ≤W c ≤0.7W out relationship

[0020] In addition, in one aspect of the present invention, the cross-section of the reflecting surface is polygonal.

[0021] In addition, in one aspect of the present invention, a plurality of the reflecting portions and the lens portions are provided, and the plurality of reflecting portions and the lens portions are arranged connectedly along an axial direction.

[0022] In order to solve the above problems, the present invention provides an illumination device, characterized by comprising: the optical component according to any one of the above; a light-emitting element, which is arranged on the light incident port side and emits light, and the width W of the light-emitting element d and the width W of the light incident port in satisfy W d <W in relationship

[0023] In order to solve the above problems, the present invention provides an image projection device, characterized by comprising: an image display unit, which is irradiated with the light from the illumination device and displays an image; a projection optical unit, which projects the light from the image display unit.

[0024] Advantages of the Invention

[0025] In the present invention, it is possible to provide an optical component, an illumination device, and an image projection device that can uniformly irradiate illumination light on a limited display area and improve the utilization efficiency of the illumination light. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic cross-sectional view showing an outline of the optical component 100 of the first embodiment.

[0027] Figure 2 It is a schematic cross-sectional view showing an outline of the illumination device of the first embodiment, Figure 2 wherein (a) shows an example in which the lens unit 20 is inserted and arranged inside the light exit port 16, Figure 2 and (b) shows an example in which the lens unit 20 and the light exit port 16 are separated and arranged.

[0028] Figure 3 It is a schematic diagram for explaining the light irradiation area in the optical component 100, Figure 3 wherein (a) schematically shows the optical path via the peripheral region 22, Figure 3 and (b) schematically shows the optical path via the central region 21, Figure 3 and (c) schematically shows the overall optical path.

[0029] Figure 4 It is a diagram showing the light irradiation areas in the comparative example and the examples. Figure 4 (a) of Figure 4 shows Comparative Example 1 using only a lens. Figure 4 (b) of Figure 4 shows Comparative Example 2 using only a TIR lens. Figure 4 (c) of Figure 4 shows the example using the optical component 100 of the first embodiment.

[0030] Figure 5 It is a schematic cross-sectional view showing the outline of the optical component 200 of the second embodiment.

[0031] Figure 6 It is a schematic diagram showing the shape of the reflecting surface 12 and the cavity 15 with the main body 11 omitted in the optical component 100 of the third embodiment. Figure 6 (a) of Figure 6 is a side view. Figure 6 (b) of Figure 6 is a top view. Figure 6 (c) of Figure 6 is a perspective view observed from the light incident port 17 side. Figure 6 (d) of Figure 6 is a perspective view observed from the light emitting surface 24 side.

[0032] Figure 7 It is a schematic diagram showing the shape of the reflecting surface 12 and the cavity 15 with the main body 11 omitted in the optical component 100 of the fourth embodiment. Figure 7 (a) of Figure 7 is a side view. Figure 7 (b) of Figure 7 is a perspective view observed from the light emitting surface 24 side. Figure 7 (c) of Figure 7 is a perspective view observed from the light incident port 17 side. Detailed Embodiments

[0033] (First Embodiment)

[0034] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. The same or equivalent components, parts, and processes shown in the respective drawings are denoted by the same reference numerals, and repeated descriptions will be appropriately omitted. Figure 1 It is a schematic cross-sectional view showing the outline of the optical component 100 of the present embodiment. As Figure 1 shown, the optical component 100 includes a reflecting portion 10 and a lens portion 20.

[0035] The reflecting portion 10 is a portion that reflects the light irradiated from the light source and causes it to reach a part of the lens portion 20. As Figure 1 shown, the reflecting portion 10 includes a main body 11, a reflecting surface 12, a top surface 13, a bottom surface 14, a cavity 15, a light emitting outlet 16, and a light incident port 17. The lens portion 20 is disposed on the light emitting outlet 16 side of the reflecting portion 10.

[0036] The main body portion 11 forms the outer shape of the reflecting portion 10, and is a portion that forms a cavity 15 inside and a reflecting surface 12 on the inner surface. In Figure 1 shows a cross-sectional view of the optical component 100 along the width direction. The main body portion 11 extends in a direction perpendicular to the paper surface, and a plurality of cavities 15 are provided in the direction perpendicular to the paper surface. In addition, in Figure 1 shows the main body portion in the shape of a thick-walled block as the main body portion 11, but the shape or structure of the main body portion 11 is not limited, and it may also be a thin-walled structure along the reflecting surface 12. In addition, the material constituting the main body portion 11 is not limited, and it may be composed of a transparent or non-transparent resin material, or may be composed of a ceramic material or a metal material.

[0037] The reflecting surface 12 is a curved surface portion formed on the inner surface of the main body portion 11 and reflects a part of the light incident from the light incident port 17. The cross-section of the reflecting surface 12 along the light irradiation axis direction (left-right direction in the figure) is a parabolic shape, an ellipsoidal shape, or a free-form surface shape. The reflecting surface 12 may be formed as a rotation surface centered on the light irradiation direction, or may be formed as a curved surface shape extending in the depth direction and the up-down direction with respect to the paper surface. A cavity 15 is formed inside the reflecting surface 12, a light exit port 16 is provided on the top surface 13 side, and a light incident port 17 is provided on the bottom surface 14 side. The reflecting surface 12 may be configured to reflect light by performing mirror processing on the inner surface of the material constituting the main body portion 11, or a reflective film such as a metal film with a high reflectivity may be formed on the inner surface of the main body portion 11 using a vapor deposition method or a plating method.

[0038] The top surface 13 is the surface on the light exit side of the main body portion 11. The bottom surface 14 is the surface on the light incident side of the main body portion 11. The cavity 15 is a recess provided inside the main body portion 11, and is connected to the light exit port 16 on the top surface 13 side and to the light incident port 17 on the bottom side. The light exit port 16 is an opening provided on the light exit side of the reflecting surface 12. The light incident port 17 is an opening provided on the light incident side of the reflecting surface 12. In Figure 1 the illustration is omitted, but a holding portion for holding the lens portion 20 may also be provided on the top surface 13. In addition, a fixing portion for mounting and fixing on the mounting substrate 40 described later may also be provided on the bottom surface 14.

[0039] The lens portion 20 is disposed at the light exit port 16 of the reflecting portion 10, and is a portion through which the light irradiated from the light source and the light reflected by the reflecting portion 10 are incident and refracted. As Figure 1 shown, the lens portion 20 includes a central region 21, a peripheral region 22, light incident surfaces 21a, 22a, a boundary portion 23, and a light exit surface 24. The material constituting the lens portion 20 is not limited, and as long as it can transmit and refract visible light well, a known resin material or glass material can be used.

[0040] The central region 21 is the region located at the center of the lens portion 20 and is set to have a diopter greater than that of the peripheral region 22. The light incident surface 21a is on the side of the reflection portion 10 of the central region 21, and the light emitting surface 24 is on the side opposite to the reflection portion 10. In Figure 1 , as the central region 21, a convex lens shape in which the light incident surface 21a protrudes in the direction of the light emitting port 16 is shown, but as long as the conditions of being located at the center of the lens portion 20 and having a diopter greater than that of the peripheral region 22 are satisfied, the surface shape of the lens is not limited. As an example, it may be a convex lens in which the light emitting surface 24 protrudes in the light emitting direction (the right direction in the figure), or it may be a meniscus-shaped lens.

[0041] The peripheral region 22 is the region provided around the central region 21 and is set to have a diopter less than that of the central region 21. The light incident surface 22a is on the side of the reflection portion 10 of the peripheral region 22, and the light emitting surface 24 is on the side opposite to the reflection portion 10. In Figure 1 , as the peripheral region 22, a convex lens shape is shown, in which the outermost periphery of the convex lens shape is thin and becomes thicker toward the central region 21 and protrudes in the direction of the light emitting port 16, but as long as the conditions of being provided on the outer peripheral side of the central region 21 and having a diopter less than that of the central region 21 are satisfied, the surface shape of the lens is not limited. As an example, it may be a convex lens in which the light emitting surface 24 becomes thicker from the outermost periphery toward the central region 21 and protrudes in the light emitting direction, or it may be a meniscus-shaped lens.

[0042] The boundary portion 23 is the portion that forms the boundary between the central region 21 and the peripheral region 22. In Figure 1 , as the boundary portion 23, an example in which the curvature of the central region 21 and the peripheral region 22 changes discontinuously and forms a curved region on the surface is shown, but the curvature of the central region 21 and the peripheral region 22 may also change gradually. In the case where the curvature changes gradually, the boundary at which the central region 21 and the peripheral region 22 switch is not clear, and the diopter of both also changes gradually. In this case, the change point in the change of the diopter, or the middle of the maximum value and the minimum value of the diopter can be regarded as the boundary portion 23.

[0043] The light emitting surface 24 is the surface that forms the light emitting side of the lens portion 20. In Figure 1 , as the light emitting surface 24, an example in which the light emitting sides of the central region 21 and the peripheral region 22 are set as one plane is shown, but the surface shape of the light emitting surface 24 is not limited. As an example, the light emitting sides of the central region 21 and the peripheral region 22 may intersect at different angles, or may be formed by different curved surface shapes respectively.

[0044] Figure 2 is a schematic cross-sectional view showing an outline of the lighting device of the present embodiment, Figure 2Example (a) shows the case where the lens unit 20 is inserted and disposed inside the light exit port 16. Figure 2 Example (b) shows the case where the lens unit 20 and the light exit port 16 are separately disposed. As Figure 2 shown, the lighting device includes a reflection unit 10 and a lens unit 20 that constitute the optical component 100, a light emitting element 30, and a mounting substrate 40. In addition, Figure 2 the lighting device shown is used in an image projection device that includes an image display unit for displaying an image and a projection optical unit for projecting light from the image display unit.

[0045] In the image projection device, the light irradiated from the lighting device is irradiated onto the display area of the image display unit, and the image displayed on the display area is projected by the projection optical unit. The image projection device is, for example, housed in the instrument panel of a vehicle in a head-up display (HUD), and a virtual image is formed by projecting an image from the image projection device via a windshield or the like. The light irradiated from the image projection device is reflected by a projection optical unit such as a plane mirror or a free-form mirror as needed, and guided to the driver's eyes via the windshield, and thus is recognized.

[0046] The light emitting element 30 is a component that is disposed on the light incident port 17 side of the reflection unit 10 and irradiates light to the reflection unit 10 and the lens unit 20. As an example, the light emitting element 30 is a semiconductor light emitting element such as an LED (Light Emitting Diode), and is arranged in a predetermined direction (a direction perpendicular to the Figure 2 plane of the paper). The light emitting color of the light emitting element 30 is not particularly limited, but in the present embodiment, as an example, it is set to white. It should be noted that in the present embodiment, the number of arrangements of the light emitting elements 30 is set to one row, but it may be set to two or more rows, or may be arranged not in a linear shape but in a manner of depicting an arc or a curve so that the lens shape and arrangement of the reflection unit 10 correspond to the arrangement shape of the LEDs. In addition, the light emitting element 30 is not limited to an LED, and may be an organic EL (Electro Luminescence) element or the like.

[0047] The mounting substrate 40 is a component that mounts the light emitting element 30 and supplies power to the light emitting element 30. Although not shown in Figure 2 , wirings are formed on the surface or inside of the mounting substrate 40, and a plurality of electronic components or terminal portions may be mounted on the mounting substrate 40. In addition, a drive circuit of the light emitting element 30 may be constituted by wirings and electronic components. Power and control signals are sent to the mounting substrate 40 from the outside via the terminal portions, and the light emitting element 30 emits light based on the control signals.

[0048] Light traveling in the light emission direction from the light emitted by the light emitting element 30 enters the cavity 15 through the light incident port 17, travels in the cavity 15, and is incident on the light incident surface 21a of the central region 21 and the light incident surface 22a of the peripheral region 22. In addition, light traveling obliquely with respect to the light emission direction from the light emitted by the light emitting element 30 enters the cavity 15 through the light incident port 17, reaches the reflection surface 12 of the reflection portion 10, and is reflected. The light reflected by the reflection surface 12 travels in the cavity 15 and is incident on the light incident surface 22a of the peripheral region 22. The light incident on the light incident surfaces 21a and 22a is refracted by the optical power of the central region 21 and the peripheral region 22, respectively, and is irradiated in the light irradiation direction from the light emission surface 24.

[0049] As Figure 2 shown, preferably, the width W d of the light emitting surface of the light emitting element 30 in is smaller than the width W d of the light incident port 17, in satisfying the relationship of W Figure 2 < W d < W in . In d , an example is shown in which the upper end surface of the light emitting element 30 and the bottom surface 14 of the reflection portion 10 are at the same level, but the light emitting element 30 can also be inserted and arranged in the cavity 15 from the light incident port 17. By the widths of the light emitting element 30 and the light incident port 17 satisfying the relationship of W

[0050] < W Figure 2 < W c < W out , the light emitted from the light emitting element 30 can be efficiently taken into the cavity 15. Here, the width W c of the light emitting surface of the light emitting element 30 out corresponds to the chip size when the light emitting element 30 is an LED chip, and corresponds to the width on the light emitting surface such as the lens portion or the window portion when the light emitting element 30 is an LED package. c out out c out c c out c c c is smaller than this range, the amount of light refracted by the central region 21 decreases, and it is difficult to ensure the amount of light near the center in the irradiation region, making uniform light irradiation difficult. In addition, if W cIf it is larger than this range, the amount of light reflected by the reflecting surface 12 and refracted by the peripheral region 22 decreases, and it becomes difficult to ensure the amount of light near the outer periphery within the irradiation region, making it difficult to achieve uniform light irradiation.

[0051] In Figure 2 In the example shown in (a) of [], the central region 21 has a convex lens shape with a light incident surface 21a protruding toward the reflecting portion 10, and at least a part of the light incident surface 21a is inserted into the cavity 15 closer to the inside of the cavity 15 (on the light incident port 17 side) than the light exit port 16. In other words, when the light emission direction is set as positive and the light incident direction is set as negative with reference to the top surface 13 position of the light exit port 16, the distance D between the most protruding position of the light incident surface 21a and the top surface 13 position becomes negative. By inserting the light incident surface 21a into the cavity 15, the central region 21 and the peripheral region 22 can be arranged closer to the light emitting element 30, making it easier to define the light irradiation range.

[0052] In Figure 2 In the example shown in (b) of [], the central region 21 has a convex lens shape with a light incident surface 21a protruding toward the reflecting portion 10, and the front end of the light incident surface 21a is arranged at a separation distance D from the light exit port 16. In other words, the distance D between the most protruding position of the light incident surface 21a and the top surface 13 position becomes positive. By arranging the light incident surface 21a and the light exit port 16 separately, a larger area of the central region 21 can be ensured. Additionally, preferably, the distance D between the front end of the light incident surface 21a of the central region 21 and the light exit port 16 satisfies the relationship D ≤ 0.5W out If the distance D is larger than this range, the light traveling in the cavity 15 from the light emitting element 30 diffuses excessively, making it difficult to irradiate light uniformly over a limited small range.

[0053] Figure 3 is a schematic diagram for explaining the light irradiation region in the optical component 100, Figure 3 In (a) of [], the light path via the peripheral region 22 is schematically shown, Figure 3 In (b) of [], the light path via the central region 21 is schematically shown, Figure 3 In (c) of [], the overall light path is schematically shown. The point L in the figure represents the light emission center of the light emitting element 30, indicating the light irradiation position when the light emitting element 30 is regarded as a point light source. The actual light emitting element 30 has a light emitting surface with a finite area, but in Figure 3 , for simplicity of explanation, the case of using a point light source is described. The arrows shown in the figure represent the light traveling paths, but for schematic representation of the light paths, the description is simplified, and the density of the arrows does not accurately represent the light quantity or brightness. Additionally, the light refraction in the lens portion 20 is also schematically shown and does not accurately represent the light refraction.

[0054] AsFigure 3 As shown in (a) of [reference], the light traveling in a direction inclined at an angle greater than a specified angle with respect to the light emission direction (the right direction in the figure) among the light emitted from the light emitting element 30 is incident on the reflecting surface 12 and reflected. The light reflected by the reflecting surface 12 travels in the cavity 15 and is incident on the peripheral region 22. The incident angle of the light incident on the peripheral region 22 when it reaches the light incident surface 22a varies depending on the shape and position of the reflecting surface 12. Although the optical power of the peripheral region 22 is smaller than that of the central region 21, since it has a positive optical power, it converges slightly toward the center of the irradiation region.

[0055] As Figure 3 shown in (b) of [reference], the light traveling in a direction inclined at an angle smaller than the specified angle with respect to the light emission direction among the light emitted from the light emitting element 30 travels in the cavity 15 and is directly incident on the light incident surface 21a of the central region 21 and the light incident surface 22a of the peripheral region 22. The light directly incident from the light emitting element 30 on the light incident surfaces 21a and 22a spreads radially from the point L. Here, since the optical power of the peripheral region 22 is smaller than that of the central region 21, the light incident on the light incident surface 22a converges slightly. In addition, the light incident on the light incident surface 21a converges with an optical power greater than that of the peripheral region 22, but converges slightly because the incident angle when it reaches the light incident surface 21a is small.

[0056] As Figure 3 shown in (c) of [reference], the light reflected by the reflecting surface 12 and incident on the light incident surface 22a and the light directly incident on the light incident surfaces 21a and 22a are superimposed and irradiated. As described above, the light incident on the light incident surface 21a is refracted and converged with a large optical power, and the light incident on the light incident surface 22a is refracted and converged with a small optical power. Since the light emitted from the light emitting element 30 generally has a light distribution close to a Gaussian distribution, by appropriately setting the relationship between the optical powers of the central region 21 and the peripheral region 22, it is possible to irradiate the center and the outer periphery of the irradiation region with light uniformly.

[0057] In Figure 3 [reference], an example in which the light reflected by the reflecting surface 12 is incident on the light incident surface 22a at different angles is shown, and an example in which the light refracted by the peripheral region 22 intersects is shown. However, in the case where the reflecting surface 12 is formed in a parabolic shape, by arranging the point light source L at the focal position of the paraboloid, the light reflected by the reflecting surface 12 can be made into substantially parallel light and incident on the light incident surface 22a. Thereby, it becomes easy to irradiate the irradiation region with the light refracted by the peripheral region 22 at an appropriate density. In addition, in the case where the reflecting surface 12 is formed of a free-form mirror, the light emission port from the light emitting element 30 can be set as a light emitting surface having a finite area instead of the point light source L, and the shape of the reflecting surface 12 can be set so as to obtain an appropriate light distribution.

[0058] Figure 4 It is a diagram showing the light irradiation areas in the comparative example and the example. Figure 4 In (a) of Figure 4 , Comparative Example 1 using only a lens is shown. Figure 4 In (b) of Figure 4 , Comparative Example 2 using only a TIR lens is shown. Figure 4 In (c) of Figure 4 , the example using the optical component 100 of the first embodiment is shown. In the figure, the schematic diagram shown on the left represents the shape of each lens, and the photograph shown on the right represents the light beam irradiated to the image display unit of the image projection device. The area surrounded by the black solid line in the photograph shown on the right corresponds to the irradiation area (display area) where the image is displayed and light is irradiated. Hereinafter, taking the entire image display unit and the light beam in the irradiation area of Comparative Example 2 using a TIR lens as a reference (100%), the relative light beam will be described.

[0059] In Comparative Example 1 using the convex lens shown in (a) of Figure 4 Figure 4 the light beam of the entire image display unit is 43.7%, and the light beam of the irradiation area is 86.9%. In Comparative Example 1, since the light is converged by the convex lens, the light beam can be concentrated on the irradiation area, but the light irradiated from the light-emitting element 30 to the outer side direction cannot be effectively utilized. Therefore, it is difficult to improve the brightness and recognizability of the virtual image projected by the image projection device.

[0060] In Comparative Example 2 using the TIR lens shown in (b) of Figure 4 Figure 4 light can be irradiated uniformly over the entire image display unit, but a lot of light is also irradiated to the area outside the irradiation area. The reason is that the reflection surface of the TIR lens uses total reflection caused by the refractive index difference, and there are physical limits in the tilt angle and size of the reflection surface. Therefore, in Comparative Example 2 using a TIR lens, it is difficult to concentrate the light beam on the narrow irradiation area to improve the brightness and recognizability of the virtual image.

[0061] In the example using the optical component 100 of the first embodiment shown in (c) of Figure 4 Figure 4 the light beam of the entire image display unit is 97.5%, and the light beam of the irradiation area is 169%. Therefore, in Example 1, the light beam can be concentrated on the irradiation area in a narrower range compared to Comparative Example 2 to improve the brightness and recognizability of the virtual image. In addition, from the photograph shown on the right side of (c) of Figure 4 Figure 4 it can be seen that the irradiation light can be uniformly irradiated to the limited irradiation area (display area), and the utilization efficiency of the irradiation light can be improved.

[0062] As described above, in the optical component 100, the lighting device, and the image projection device according to the present embodiment, the lens unit 20 is disposed at the light exit 16 of the reflection unit 10, and the optical power of the central region 21 of the lens unit 20 is greater than that of the peripheral region 22. Therefore, it is possible to separately set the light irradiation regions where light directly incident from the light-emitting element 30 to the central region 21 and the peripheral region 22, and the light irradiation region where light reflected by the reflection unit 10 and incident on the peripheral region 22. Thereby, it is possible to uniformly irradiate the irradiation light on a limited display region and improve the utilization efficiency of the irradiation light.

[0063] (Second Embodiment)

[0064] Next, use Figure 5 to describe the second embodiment of the present invention. Descriptions of the content repeated with the first embodiment are omitted. Figure 5 FIG. is a schematic cross-sectional view showing an outline of the optical component 200 according to the present embodiment. The optical component 200 includes a plurality of reflection units 10 and a lens unit 20, and the reflection unit 10 and the lens unit 20 are connected and formed integrally along an axial direction (the left-right direction in the figure) and arranged. In addition, at both ends of the reflection unit 10, lens holding portions 25 are erected on the top surface 13, and at both ends of the lens unit 20, the peripheral regions 22 are held by the lens holding portions 25. In addition, in the optical component 200, the adjacent peripheral regions 22 of the lens unit 20 are formed integrally, and the light exit surface 24 constitutes a single plane as a whole.

[0065] In the present embodiment, in the optical component 100, the lighting device, and the image projection device, the lens unit 20 is also disposed at the light exit 16 of the reflection unit 10, and the optical power of the central region 21 of the lens unit 20 is greater than that of the peripheral region 22. Therefore, it is possible to separately set the light irradiation regions where light directly incident from the light-emitting element 30 to the central region 21 and the peripheral region 22, and the light irradiation region where light reflected by the reflection unit 10 and incident on the peripheral region 22. Thereby, it is possible to uniformly irradiate the irradiation light on a limited display region and improve the utilization efficiency of the irradiation light.

[0066] (Third Embodiment)

[0067] Next, use Figure 6 to describe the third embodiment of the present invention. Descriptions of the content repeated with the first embodiment are omitted. Figure 6 FIG. is a schematic view showing the shape of only the reflection surface 12 and the cavity 15 with the main body portion 11 omitted in the optical component 100 according to the present embodiment, Figure 6 where (a) is a side view, Figure 6 where (b) is a top view, Figure 6 where (c) is a perspective view observed from the light incident port 17 side, Figure 6 where (d) is a perspective view observed from the light exit surface 24 side.

[0068] As Figure 6 shown in (a) to Figure 6 shown in (d) of this embodiment, the reflecting surface 12 of the reflecting portion 10 is constituted by four curved surfaces, and in a cross section perpendicular to the light emission direction, the reflecting surface 12 is set as a square. By setting the cross section of the reflecting surface 12 as a square, the area of the light emission port 16 can be enlarged, and the density when arranging a plurality of optical components 100 can be increased, and the aperture ratio of the light emission port 16 can be increased to improve the utilization efficiency of light. In Figure 6 , an example where the cross section of the reflecting surface 12 is a square is shown, but as long as the cross section of the reflecting surface 12 is a polygonal shape such as a triangle or a hexagon, the density when arranging a plurality of optical components 100 can be increased.

[0069] (Fourth Embodiment)

[0070] Next, Figure 7 the fourth embodiment of the present invention will be described. The description of the content repeated with the first embodiment is omitted. Figure 7 is a schematic diagram showing the shape of only the reflecting surface 12 and the cavity 15 with the main body portion 11 omitted in the optical component 100 of this embodiment, Figure 7 (a) of Figure 7 is a side view, Figure 7 (b) of

[0071] As Figure 7 shown in (a) to Figure 7 shown in (c) of this embodiment, the reflecting surface 12 of the reflecting portion 10 is constituted by a rotating curved surface with the light emission direction as the central axis, and in a cross section perpendicular to the light emission direction, the reflecting surface 12 is set as a circle. By setting the cross section of the reflecting surface 12 as a circle, the light irradiated from the light emitting element 30 can be uniformly irradiated around the central axis.

[0072] The present invention is not limited to the above-described embodiments, and various changes can be made within the scope shown in the claims, and embodiments obtained by appropriately combining the technical solutions separately disclosed in different embodiments are also included in the technical scope of the present invention.

[0073] This international application claims the priority based on Japanese Patent Application No. 2022-200646 filed on December 15, 2022, and the entire content of the Japanese Patent Application No. 2022-200646 is incorporated herein by reference.

[0074] The above description of specific embodiments of the present invention is presented for illustrative purposes. These descriptions are comprehensive and are not intended to limit the present invention in the described manner. Obviously, those skilled in the art can make many modifications or changes based on the above description.

[0075] Description of Reference Numerals

[0076] 100, 200: Optical components

[0077] 10: Reflective portion

[0078] 20: Lens portion

[0079] 30: Light-emitting element

[0080] 40: Mounting substrate

[0081] 11: Main body portion

[0082] 12: Reflective surface

[0083] 13: Top surface

[0084] 14: Bottom surface

[0085] 15: Cavity

[0086] 16: Light exit port

[0087] 17: Light incident port

[0088] 21: Central region

[0089] 21a, 22a: Light incident surface

[0090] 22: Peripheral region

[0091] 23: Boundary portion

[0092] 24: Light emitting surface

[0093] 25: Lens holding portion.

Claims

1. An optical component, characterized in that, Comprising: A reflecting part, on the inner surface of which a reflecting surface is formed, having a light incident opening at one end of the reflecting surface and a light emitting opening at the other end of the reflecting surface; A lens part, which is disposed at the light emitting opening of the reflecting part, The lens part has a central area located at the center and a peripheral area provided around the central area, and the optical power of the central area is greater than that of the peripheral area.

2. The optical component according to claim 1, wherein: The distance D between the light exit and the central region and the width W of the light exit out satisfy D ≤ 0.5W out relationship.

3. The optical component according to claim 2, wherein: The central area has a convex lens shape in which the light incident surface protrudes in the direction of the reflecting part.

4. The optical component according to claim 3, wherein: At least a part of the light incident surface is inserted to the side of the light incident opening with respect to the light emitting opening.

5. The optical component according to claim 1, wherein: The width W of the central region c and the width W of the light emission outlet out satisfy 0.3W out ≤W c ≤0.7W out relationship.

6. The optical component according to claim 1, wherein: The cross section of the reflecting surface is polygonal.

7. The optical component according to claim 1, wherein: A plurality of the reflecting parts and the lens parts are provided, and the plurality of reflecting parts and the lens parts are connected and arranged along an axial direction.

8. A lighting device, characterized in that, Comprising: The optical component according to any one of claims 1 to 7; A light emitting element, which is disposed on the light incident opening side and emits light, The width W of the light-emitting element d and the width W of the light incident port in satisfy the relationship of W d <W in as follows.

9. An image projection device, characterized in that, Comprising: The lighting device according to claim 8; An image display part, which is irradiated with the light from the lighting device and displays an image; A projection optical part, which projects the light from the image display part.

Images