Lens for blind spot monitor, blind spot monitor light-emitting unit, and blind spot monitor light-emitting section

Abstract

This invention provides a lens for a blindspot monitor, a blindspot monitor light-emitting unit, and a blindspot monitor light-emitting section that suppress uneven illumination of icons. [Solution] The blind spot monitor lens 18 has a front plate 18a, a rear plate 18c positioned opposite the front plate 18a on the rear side with a gap 19 in between, a connecting portion 18d that integrally connects the front plate 18a and the rear plate 18c around the gap 19, and an opening 18e that connects the gap 19 to the space outside the gap 19. The front plate 18a has the property of transmitting light while diffusing it. The rear plate 18c has the property of reflecting light while diffusing it on the front side of the rear plate 18c that faces the front plate 18a. The opening 18e is configured so that light from the light source 20 can be introduced into the gap 19 through the opening 18e. The light from the light source 20 that is transmitted from the rear side to the front side of the front plate 18a is used to illuminate the icon.

Description

Technical Field

[0001] This invention relates to a lens for a blind spot monitor, a blind spot monitor light emitting unit, and a blind spot monitor light emitting portion, and suppresses uneven light emission of an icon.

Background Art

[0002] A blind spot monitor is a device mounted on a vehicle, which detects another vehicle approaching the host vehicle and emits an icon of a predetermined shape to notify the driver of the host vehicle of the approach of the other vehicle. The light emitting portion of the blind spot monitor includes a lens that receives light from a light source and emits surface light. The surface-emitted light is shaped by passing it through a light transmission portion on which an icon is drawn, so that a display that emits light in the shape of the icon is obtained. A conventional lens for a blind spot monitor is generally a one-piece thick plate made of a light guide having a lens cut on its surface (for example, the one described in Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] [[ID= / / 34]] >Since a conventional lens is composed of a single thick plate, it is difficult to obtain a light emitting surface with uniform brightness over the entire surface due to sink marks during molding, and uneven light emission of the icon is likely to occur. This invention provides a lens for a blind spot monitor, a blind spot monitor light emitting unit, and a blind spot monitor light emitting portion that solve the problems in the above conventional technology and suppress uneven light emission of an icon.

Means for Solving the Problems

[0005] The blind spot monitor lens of this invention comprises a front plate, a rear plate positioned opposite the front plate on the rear side with a gap between them, a connecting portion that integrally connects the front plate and the rear plate around the gap, and an opening that connects the gap to the space outside the gap. The front plate is configured to transmit light while diffusing it, and the rear plate is configured so that the front side of the rear plate facing the front plate reflects light while diffusing it. The opening is configured to allow light from a predetermined light source to enter the gap through the opening, and the light from the light source that passes from the rear side to the front side of the front plate can be used to illuminate an icon. With this lens, light from a light source is introduced into the gap between the front plate and the rear plate, and the light introduced is reflected while diffusing by the rear plate and transmitted while diffusing by the front plate, causing the front surface of the front plate to emit light. In this case, since a gap is arranged between the front plate and the rear plate, the front plate and the rear plate can be made to be thin. Therefore, compared to the case where the lens is constructed from a thick plate with a total size equal to the front plate, gap, and rear plate combined, it is possible to suppress sink marks during molding and reduce uneven illumination of the icon.

[0006] In the lens of this invention, the connecting portion is configured to connect the front plate and the rear plate along the circumferential direction of the gap, and the gap can be surrounded by the connecting portion and formed into a bag shape. As a result, since the gap is surrounded by the connecting portion and formed into a bag shape, it is possible to suppress the leakage of light that enters the gap to the surrounding area of ​​the gap, and to efficiently emit light from the front surface of the front plate.

[0007] In the lens of this invention, the opening can be formed between the front plate and the rear plate. This allows the opening to be formed by withdrawing the mold that forms the void when manufacturing the lens by injection molding.

[0008] The rear plate can be positioned at an angle to the front plate, facing the direction of the opening. This allows light entering the gap to be efficiently reflected by the rear plate and incident on the front plate, thereby efficiently emitting light from the front surface of the front plate.

[0009] The lens of this invention may be made from a single molded product of a cloudy plastic material that has the property of transmitting light while diffusing it. This makes it possible to easily and inexpensively manufacture a lens that exhibits the effects of this invention.

[0010] The blind spot monitor light-emitting unit of this invention comprises a light source and a lens that receives and transmits light from the light source and emits it from a predetermined light-emitting surface. The lens comprises a front plate constituting the light-emitting surface, a rear plate positioned opposite the front plate on the back side with a gap between them, and an opening that connects the gap to the space outside the gap. The front plate is configured to transmit light while diffusing it, and the rear plate is configured so that the front side of the rear plate facing the front plate reflects light while diffusing it. The light from the light source is arranged to enter the gap through the opening. This makes it possible to suppress uneven illumination of the icon.

[0011] The blind spot monitor light-emitting unit of this invention comprises a light source, a lens that receives and transmits light from the light source and emits it from a predetermined light-emitting surface, and a light-transmitting unit positioned in front of the light-emitting surface and shaping the cross-sectional shape of the light emitted from the light-emitting surface in a direction perpendicular to the optical axis into a predetermined icon shape. The lens comprises a front plate constituting the light-emitting surface, a rear plate positioned opposite the front plate on the back side with a gap between them, and an opening that connects the gap to the space outside the gap. The front plate is configured to transmit light while diffusing it, and the rear plate is configured so that the front side of the rear plate facing the front plate reflects light while diffusing it. Light from the light source is directed into the gap through the opening, and the light source is positioned so that it is not visible through the light-transmitting unit when the light-emitting surface is viewed from the front. As a result, the light source is not directly visible or is difficult to see through the light-emitting surface, thus suppressing uneven illumination of the icon due to point illumination (a state in which the light source position appears to be brightly lit as a point). [Brief explanation of the drawing]

[0012] [Figure 1] This cross-sectional side view shows an embodiment of the lens, BSM light-emitting unit, and BSM light-emitting section for a blind spot monitor (hereinafter abbreviated as "BSM") according to the present invention, showing the BSM light-emitting unit mounted on the back (rear surface, back surface) of the mirror plate of a vehicle outer mirror, and also showing the behavior of the light emitted from the illuminated light source. [Figure 2] Figure 1 is an exploded perspective view of the BSM light-emitting unit and mirror plate (for the right-side outer mirror of the vehicle), showing the mirror plate as viewed from diagonally above the front (front) side. [Figure 3A] Figures 1 and 2 are perspective views of the lens, taken from one side (left or right) diagonally above its rear surface. [Figure 3B] This is a view of the lens from the left, right, and diagonally above sides of its rear surface. [Figure 3C] This is a front view (front view, a view of the light-emitting surface from the front) of the lens. [Figure 3D] This is a rear view (back view, back view) of the same lens. [Figure 3E]This is a plan view (top view) of the lens. [Figure 3F] This is a bottom view (underside view) of the lens. [Figure 3G] This is a left side view of the same lens. [Figure 4] This diagram shows the icon display positions virtually projected onto the light-emitting surface of the lens, indicated by dashed lines, and is viewed from the same direction as Figure 3C. [Figure 5] Figure 1 shows the BSM light-emitting unit viewed from the front (light-emitting surface). [Modes for carrying out the invention]

[0013] Embodiments of this invention will now be described. Here, the directions up, down, left, right, front, and rear (back) for the outer mirror, BSM lens, BSM light-emitting unit, and BSM light-emitting section are expressed as the directions when the outer mirror equipped with the BSM light-emitting unit is mounted on a vehicle and positioned in the deployed position (non-storage position, i.e., usage position), and its mirror surface is viewed from the front. Figure 2 shows the BSM light-emitting unit 12 and BSM light-emitting section 13, which are mounted on the mirror plate 10 of the right-side outer mirror of a vehicle, disassembled into their component parts. The mirror housing of the outer mirror is not shown. The BSM light-emitting unit 12 is housed on the rear side of the mirror plate 10 within the mirror housing. This BSM light-emitting unit 12 is for the right-side mirror of the vehicle. A BSM light-emitting unit for the left-side mirror of the vehicle (not shown) has a structure symmetrical to the BSM light-emitting unit 12 for the right-side mirror of the vehicle. The BSM light-emitting unit 12 is constructed by integrally assembling the housing 14, PCB (printed circuit board) 16, and lens 18. The housing 14 is made of, for example, black opaque resin. The lower surface of the PCB 16 is equipped with LEDs 20 that constitute the light source, as well as a connector 22 and other circuit elements. The lens 18 is a BSM lens according to this invention. The BSM light-emitting unit 12 is assembled integrally by inserting the PCB 16 horizontally into the upper part of the internal space 14b through the front opening 14a of the housing 14, and fitting the lens 18 into the front opening 14a. At the rear end of the housing 14, a connector insertion opening 14c is formed for inserting an external wiring connector (not shown) into the internal space 14b and detachably connecting it to the connector 22 of the PCB 16. A light-transmitting portion 24 in a predetermined icon shape (in this case, triangular) is formed on the back surface of the mirror plate 10 at a position slightly to the right of the peripheral edge. The light-transmitting portion 24 can be formed, for example, by removing the reflective film 26 in a predetermined icon shape by etching or the like at the position where the icon is formed on the back surface of the mirror plate 10. The integrated BSM light-emitting unit 12 is attached to the back of the mirror plate 10 using double-sided adhesive tape 28. A window 28a with a predetermined icon shape is formed within the surface of the double-sided adhesive tape 28.The BSM light-emitting unit 12 is attached to the back of the mirror plate 10 by attaching one side of the double-sided adhesive tape 28 to the back of the mirror plate 10, aligning the window 28a with the light-transmitting part 24, and attaching the light-emitting surface 12a (the front surface 18a1 of the front plate 18a) of the BSM light-emitting unit 12 to the other side of the double-sided adhesive tape 28. This completes the BSM light-emitting section 13.

[0014] The structure of the lens 18 will be described with reference to Figure 3 (Figures 3A to 3G). The lens 18 is composed of a single molded product made of a translucent, opaque plastic material such as milky white, which has the property of transmitting light while diffusing it. As such a plastic material, for example, a translucent plastic material such as PMMA or PC mixed with a white coloring agent such as titanium dioxide, calcium carbonate, or antimony oxide can be used. The lens 18 can be manufactured by injection molding such a translucent, opaque plastic material such as milky white. The lens 18 has a front plate 18a and a rear plate 18c which is positioned opposite to the back side of the front plate 18a with a gap 19 in between. The front plate 18a has a predetermined thickness and is generally formed in a vertically elongated rectangular shape. To make it easily distinguishable from the left mirror lens (not shown), one of the upper left and right corners of the vertically elongated rectangle of the front plate 18a is cut diagonally to form a cut portion 18h (Figures 3C and 3D). The rear plate 18c has approximately the same thickness as the front plate 18a, and is formed in a roughly elongated rectangular shape, smaller overall than the front plate 18a. Since a gap 19 is positioned between the front plate 18a and the rear plate 18c, the front plate 18a and the rear plate 18c can each be formed with a thinner thickness. Therefore, compared to the case where the lens is constructed as a solid, thick-plate lens with the combined size of the front plate 18a, the gap 19, and the rear plate 18c, sink marks during molding can be suppressed, and uneven illumination of the icon can be suppressed. As shown in Figure 3D, the rear plate 18c has a smaller area than the front plate 18a and is positioned within the plane of the front plate 18a. The rear plate 18c is positioned at an angle upward relative to the front plate 18a. As a result, the gap 19 is formed in a wedge shape, narrowing downwards and widening upwards. The left, right, and bottom sides of the gap 19 are closed by connecting parts 18d that integrally connect the front plate 18a and the rear plate 18c. An opening 18e is formed above the gap 19, connecting the gap 19 to the space outside the gap 19. As a result, the entire perimeter of the gap 19, except for the upper opening 18e, is closed by the connecting portion 18d, forming a bag-like structure. The size of the gap 19 is set so that, when viewed from the front of the front plate 18a, the entire icon fits within the area of ​​the gap 19 (the area surrounded by the connecting portion 18d and the opening 18e).The dashed line 30 in Figure 4 indicates the position on the front surface 18a1 (light-emitting surface 12a) of the front plate 18a facing the light-transmitting portion 24 of the mirror plate 10, i.e., the position corresponding to the icon display position. The shape of the icon is formed by the light-transmitting portion 24 (Figures 1 and 2) of the mirror plate 10, which is located on the front side of the front plate 18a, and the entire front surface 18a1 of the front plate 18a emits light. At least the positions on both the front surface 18a1 and the back surface 18a2 of the front plate 18a where the icons are placed are formed as smooth surfaces without large irregularities to prevent uneven illumination of the icons. Two ribs 18f protrude from the upper part of the back surface 18a2 of the front plate 18a (positions that do not overlap the icons when viewed from the front) to support the lower surface of the PCB 16. Two protrusions 18g protrude from the lower left and right of the back surface 18a2 of the front plate 18a, which are inserted into positioning holes 14d (Figure 2) of the housing 14 to position the lens 18 in the housing 14. On the left and right sides of the vertically central portion of the back surface 18a2 of the front plate 18a, claws 18i are formed to fit into claw receiving portions 14f (Figure 2) formed at corresponding positions on the front opening 14a of the housing 14, thereby mounting the lens 18 into the front opening 14a. Figure 5 shows the state in which the lens 18 is fitted into the front opening 14a and mounted on the housing 14. The region 18c' (Figure 3B, etc.) on one side of the rear plate 18c is formed as an inclined surface that connects diagonally to the connecting portion 18d, as a result of increasing the thickness of the male mold (mold) that forms the gap 19 by build-up welding in order to increase the strength of the tip of the male mold. Therefore, the fact that the region 18c' of the rear plate 18c is formed as an inclined surface is not particularly important for the function of the rear plate 18c, and it is possible to eliminate this inclined surface (for example, by forming the entire rear plate 18c as a continuous surface such as a flat surface).

[0015] Figure 1 shows the BSM light-emitting unit 12 from Figure 2 attached to the back of the mirror plate 10 with double-sided adhesive tape 28, and the state in which the LED 20 is lit and the icon is illuminated (the light emitted from the LED 20 is indicated by the arrow 34). The PCB 16 is positioned approximately perpendicular to the surface of the mirror plate 10. The optical axis 20a of the LED 20 is positioned approximately parallel to the surface of the mirror plate 10. The LED 20 is positioned facing downwards, opposite the gap 19. The area of ​​the reflective film 26 on the back of the mirror plate 10 (Figure 1 exaggerates the thickness of the reflective film) where the icon is displayed is removed in the shape of the icon (a triangular shape in the front) to form a light-transmitting portion 24. The double-sided adhesive tape 28 has a window 28a so as not to block the light-transmitting portion 24. The LED 20 is positioned so as not to be seen through the light-transmitting portion 24 when viewed from the front of the light-emitting surface 12a (a position hidden by the opaque area around the light-transmitting portion 24).

[0016] Describe the behavior of the light 34 emitted from the LED 20. The light 34 emitted from the LED 20 is introduced into the gap 19 through the opening 18e. A part of the light 34 introduced into the gap 19 irradiates the rear plate 18c, a part of it is reflected by the front surface 18c1 of the rear plate 18c and irradiates the front plate 18a, and another part is incident from the front surface 18c1 of the rear plate 18c into the inside of the rear plate 18c, reflected by the colorant inside the plate, and emitted from the front surface 18c1 of the rear plate 18c to irradiate the back surface 18a2 of the front plate 18a. A part of the light 34 incident into the inside of the rear plate 18c passes through the rear plate 18c and exits from the back surface 18c2 of the rear plate 18c, but since it is shielded by the housing 14, there is no leakage outside the BSM light-emitting unit 12. Also, another part of the light 34 introduced into the gap 19 directly irradiates the back surface 18a2 of the front plate 18a. The light 34 (the light reflected by the rear plate 18c, the light directly coming from the LED 20, etc.) irradiated on the back surface 18a2 of the front plate 18a passes through the front plate 18a while diffusing, is shaped into an icon shape at the light transmission part 24, passes through the mirror plate 10, and is emitted to the outside. As a result, the light emission display of the icon is visually recognized from the driver's viewpoint 36. In this case, since the front plate 18a and the rear plate 18c can be formed with a thin plate thickness, compared with the case where the lens is composed of a thick plate having the combined size of the front plate 18a, the gap 19, and the rear plate 18c, sink marks during molding can be suppressed and uneven light emission of the icon can be suppressed. In particular, since the triangular icon has a large light-emitting area and uneven light emission is likely to be noticeable, the effect of suppressing uneven light emission is great. Also, since the gap 19 is configured in a bag shape with the left, right, and lower sides blocked, the amount of light leaking from the gap 19 can be suppressed and it can be efficiently used for the light emission of the icon.

[0017] In the lens of the above embodiment, except for the position of the opening through which light from the light source is incident, the entire circumference of the gap is continuously surrounded by the connecting portion to form the gap in a bag shape, but it is not limited to this. That is, except for the position of the opening through which light from the light source is incident, a part of the entire circumference of the gap can be surrounded by the connecting portion (for example, the connecting portion is provided discontinuously (i.e., divided into a plurality of locations) in the circumferential direction of the gap) to form the gap in a bag shape. Also, the gap does not necessarily have to be formed in a bag shape. Also, the location where the opening is formed is not limited to the upper part around the gap. That is, an opening can also be formed in the side part, lower part, etc. around the gap. Also, a lens cut can be made on the lens, or a reflective film or a coating film can be formed. Also, the color of the lens does not necessarily have to be white, and it can be colored such as yellow.

[0018] In the lens of the above embodiment, the front plate and the rear plate are integrally connected by the connecting portion, but it is not limited to this. That is, the front plate and the rear plate can be configured as separate components and incorporated into the BSM light-emitting unit.

[0019] In the above embodiment, no other light-transmissive member was arranged between the front surface of the front plate and the light-transmitting portion that shapes light into an icon shape, but other light-transmissive members (for example, other light diffusing plates) can also be interposed. Also, the icon shape is not limited to a triangle. Also, the icon is not limited to being displayed on a mirror surface.

Explanation of Reference Signs

[0020] 10...Mirror plate, 12...BSM (Blind Spot Monitor) light-emitting unit, 12a...Light-emitting surface (front of front panel), 13...BSM (Blind Spot Monitor) light-emitting section, 14...Housing, 14a...Front opening, 14b...Internal space, 14c...Connector insertion slot, 14d...Positioning hole, 14f...Claw receiving section, 16...PCB (Printed Circuit Board), 18...Lens, 18a...Front panel, 18a1...Front of front panel (light-emitting surface), 18a2...Back of front panel, 18c...Rear panel 18c1…Front of the rear panel, 18c2…Back of the rear panel, 18c'…Region on one side of the rear panel (left or right), 18d…Connecting part, 18e…Opening, 18f…Rib, 18g…Protrusion, 18h…Cut part, 18i…Claw, 19…Gap, 20…LED (light source), 20a…Optical axis, 22…Connector, 24…Light transmitting part, 26…Reflective film, 28…Double-sided adhesive tape, 28a…Window, 30…Approximate position corresponding to the icon display position, 34…Light emitted from the LED, 36…Driver's viewpoint

Claims

1. Front panel and A rear panel is positioned opposite the front panel on the back side with a gap in between, A connecting portion that integrally connects the front plate and the rear plate around the gap, The aforementioned void has an opening that connects it to the external space, The front plate is configured to have the property of transmitting light while diffusing it. The rear plate is configured such that the front side of the rear plate facing the front plate has the characteristic of diffusing and reflecting light. The opening is configured to allow light from a predetermined light source to enter the gap through the opening. A blindspot monitor lens configured to utilize light from the light source that passes through the front panel from the back to the front for illuminating the icon.

2. The lens for a blind spot monitor according to claim 1, wherein the connecting portion is configured to connect the front plate and the rear plate along the circumferential direction of the gap, and the gap is surrounded by the connecting portion and formed in a bag shape.

3. The blind spot monitor lens according to claim 1, wherein the opening is formed between the front plate and the rear plate.

4. The blind spot monitor lens according to claim 1, wherein the rear plate is inclined with respect to the front plate toward the direction of the opening.

5. A blind spot monitor lens according to claim 1, made from a single molded product of a cloudy plastic material having the property of transmitting light while diffusing it.

6. Light source and It has a lens that receives and transmits light from the light source and emits it from a predetermined light-emitting surface, The aforementioned lens is, The front plate constituting the light-emitting surface, A rear panel is positioned opposite the front panel on the back side with a gap in between, The aforementioned void has an opening that connects it to the external space, The front plate is configured to have the property of transmitting light while diffusing it. The rear plate is configured such that the front side of the rear plate facing the front plate has the characteristic of diffusing and reflecting light. The light from the light source is arranged to enter the gap through the opening. Blind spot monitor light-emitting unit.

7. Light source and A lens that receives and transmits light from the aforementioned light source and emits it from a predetermined light-emitting surface, It has a light-transmitting portion positioned in front of the light-emitting surface, which shapes the cross-sectional shape of the light emitted from the light-emitting surface in a direction perpendicular to the optical axis into a predetermined icon shape, The aforementioned lens is, The front plate constituting the light-emitting surface, A rear panel is positioned opposite the front panel on the back side with a gap in between, The aforementioned void has an opening that connects it to the external space, The front plate is configured to have the property of transmitting light while diffusing it. The rear plate is configured such that the front side of the rear plate facing the front plate has the characteristic of diffusing and reflecting light. The light from the light source is arranged to enter the gap through the opening. The light source is positioned so that it is not visible through the light-transmitting portion when viewed from the front of the light-emitting surface. Blind spot monitor light-emitting unit.

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