JP2014146742A - Head-up display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a head-up display capable of reducing operating noise to the outside emitted when cooling a heated component.SOLUTION: A head-up display comprises: a housing 10 in which an intake opening 35 for taking air into the inside, an exhaust opening 36 for discharging the taken-in air to the outside, and a duct 60 provided with an air passage therein are formed; a plurality of heating components 11 and 28 housed in the housing 10; and a blower 37 for taking in and discharging air. The plurality of heating components 11 and 28 are installed in a state in which they are exposed in the duct 60 through exposure holes 38 and 39 opened in a wall body 34 defining the duct 60. The blower 37 is installed inside the duct 60 forming an air passage from the intake opening 35 to the exhaust opening 36.

Description

  The present invention relates to a head-up display mounted on a vehicle or the like.

  A head-up display mounted on a vehicle or the like has a plurality of heat generating components such as a light source device and a light modulation device. Various devices have been devised in order to suppress the temperature rise due to these heat generating components.

  Similar to the head-up display, there is a projector as a product using a light source device and a light modulation device. It is important to cool the member that has generated heat in order to keep the function of the projector. A projector disclosed in Patent Document 1 includes an intake opening and an exhaust opening installed on a certain side surface, an intake duct having an intake port for taking outside air into the exterior casing, and an interior of the exterior casing. An exhaust duct having an exhaust port for exhausting the inside air to the outside, and an intake fan and an exhaust fan for performing intake and exhaust are provided. The intake port is provided with a filter that cleans the outside air to be sucked. Heat generation members such as the light source device and the light modulation device are cooled by the forced air cooling by the intake fan and the exhaust fan.

JP 2012-008179 A

  In the projector disclosed in Patent Document 1, it is necessary to operate the intake and exhaust fans in order to cool the heat generating member. However, the operating sound of these fans may be felt as an unpleasant sound for the user. In particular, the operation sound emitted from a head-up display mounted in a vehicle such as an automobile hinders comfortable driving.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a head-up display capable of reducing an external operation sound generated when a heated component is cooled.

  In order to achieve the above object, the head-up display according to the present invention is formed with an intake opening for taking air into the interior and an exhaust opening for discharging the taken-in air to the outside. A housing in which a duct that is the air passage is formed, a plurality of heat generating components housed in the housing, and a blower that takes in and discharges the air, the plurality of heat generating components, The duct is attached in an exposed state in the duct by an opening opened in a wall that defines the duct, and the blower forms the air passage from the intake opening to the exhaust opening. It is characterized in that it is installed inside.

  The air blower may be disposed at a substantially middle point between the intake opening and the exhaust opening.

  The plurality of heat generating components may include a light modulation device disposed closer to the intake opening than the exhaust opening, and a light source device disposed closer to the exhaust opening than the intake opening. Good.

  A dustproof filter that covers the intake opening may be further provided.

  The casing is composed of a first casing and a second casing, and a wall body that defines the duct is formed by combining the first casing and the second casing formed respectively. The duct may be formed.

  A heat sink projecting into the duct may be attached to the heat generating component.

  ADVANTAGE OF THE INVENTION According to this invention, the head-up display which can reduce the external operation sound emitted when cooling the component which generate | occur | produced heat | fever can be provided.

Schematic which showed a mode that the head-up display which concerns on embodiment of this invention was mounted in the vehicle. The perspective view of the head up display concerning the embodiment of the present invention. It is the schematic which shows a part (lower part) of the head-up display which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is the arrow view IIIb- in (a). Sectional drawing shown by IIIb. It is the schematic which shows a part (upper part) of the head-up display which concerns on the 1st Embodiment of this invention, (a) is a top view, (b) is arrow view IVb-IVb in (a). FIG. 1 is a cross-sectional view of a head-up display according to a first embodiment of the present invention. The schematic plan view which showed the inside of the head-up display which concerns on the 2nd Embodiment of this invention.

  Hereinafter, a head-up display according to an embodiment of the present invention will be described with reference to the drawings. The head-up display 1 according to this embodiment is provided in a dashboard 102 of a vehicle 100 as shown in FIG. The head-up display 1 is a device for causing the driver 110 to visually recognize the virtual image 120 of the display image by reflecting the display image with the windshield 101. Note that the virtual image 120 in the drawing is schematically shown for easy understanding.

  FIG. 2 shows an appearance of the head-up display 1 according to the embodiment of the present invention. As shown in the figure, the outer shape of the head-up display 1 is formed by fitting (merging) the lower housing 10 (first housing) and the upper housing 50 (second housing). . A transparent cover glass 52 is fitted into the opening 51 formed in the upper housing 50. The light of the display image displayed by the head-up display 1 is emitted through the cover glass 52.

  Next, the head-up display according to the first embodiment of the present invention will be described. As shown in FIG. 3A, various components of the head-up display 1 are accommodated in the lower housing 10. Therefore, details of each component of the head-up display 1 on the light path will be described in the order of the light path.

  As a light source device for the head-up display 1, a red LED 12, a green LED 13, and a blue LED 14 are attached on a metal circuit board 11. The red LED 12, the green LED 13, and the blue LED 14 receive power supply from the metal circuit board 11, and emit red, green, and blue light, respectively. The metal circuit board 11 is made of a material that is lightweight but has high thermal conductivity, such as an aluminum material. Each light emitted from the red LED 12, the green LED 13, and the blue LED 14 is incident on collimator lenses 15, 16, and 17 disposed so as to face the LEDs.

  The collimator lenses 15, 16, and 17 are made of a transparent resin such as polycarbonate. Each collimator lens 15, 16, 17 collimates incident light and emits the collimated light to various mirrors.

  Red light collimated from the collimator lens 15 enters the dichroic mirror 18. The dichroic mirror 18 has an optical characteristic of reflecting red light and transmitting green and blue light. The dichroic mirror 18 is formed by coating a glass substrate with a thin film having such optical characteristics.

  Green light collimated from the collimator lens 16 enters the dichroic mirror 19. The dichroic mirror 19 has an optical characteristic of reflecting green light and transmitting blue light. The dichroic mirror 19 is formed by coating a glass substrate with a thin film having such optical characteristics.

  Blue light collimated from the collimator lens 17 enters the plane mirror 20. The plane mirror 20 has an optical characteristic of reflecting blue light. The flat mirror 20 is formed by coating a glass substrate with a thin film having such optical characteristics. Thus, the light of each color reflected by the dichroic mirrors 18 and 19 and the plane mirror 20 is coaxially emitted toward the condenser lens 21.

  The condenser lens 21 is made of a transparent resin such as polycarbonate. The condenser lens 21 condenses the coaxial light of each color and emits it to the light tunnel 22.

  The light tunnel 22 is formed by bonding four plane mirrors so as to form a hollow column with the reflection surface inside. The light of each color that has passed through the light tunnel 22 is mixed, and uniform light without color unevenness can be obtained. The light tunnel 22 emits the uniformed light to the first relay lens 23.

  The first relay lens 23 is made of a transparent resin such as polycarbonate. The first relay lens 23 forms an image of light incident from the light tunnel 22 so as to have an appropriate irradiation size by a light modulation device to be described later, and emits the light to the plane mirror 24. The flat mirror 24 is a glass substrate on which a metal such as aluminum is deposited. The plane mirror 24 bends the optical path and emits the incident light to the second relay lens 25 in order to reduce the internal space of the lower housing 10. The second relay lens 25 is made of a transparent resin such as polycarbonate. The second relay lens 25 forms an image of the light incident from the plane mirror 24 so as to have an appropriate irradiation size by a light modulation device to be described later, and emits the light to the prism 26.

  The prism 26 is made of a glass substrate, and emits light incident from the second relay lens 25 to a light modulation device to be described later. The prism 26 plays a role of guiding the light emitted from the light modulation device to the projection lens device 27.

  The light modulation device of the head-up display 1 includes a DMD 28 (Digital Micromirror Device) which is a light modulation element, and an internal heater 29 provided in the DMD 28. The DMD 28 modulates red light, green light, and blue light incident from the prism 26 in accordance with a video signal input from the outside. Note that the DMD 28 cannot reflect 100% of incident light. For this reason, the DMD 28 has a problem that pixel defects are liable to occur in a high temperature environment due to heat generation. On the other hand, the internal heater 29 is provided to ensure the operation of the DMD 28 in a low temperature environment. The internal heater 29 raises the temperature of the DMD 28 in a low temperature environment.

  The projection lens device 27 includes a plurality of lens groups having one or a plurality of lenses. The projection lens device 27 has a function of adjusting the focus, and emits light for enlarging and projecting onto a screen 31 described later to the plane mirror 30.

  The plane mirror 30 is obtained by depositing a metal such as aluminum on a glass substrate. The plane mirror 30 bends the optical path and emits incident light to the screen 31 in order to reduce the internal space of the lower housing 10.

  The screen 31 is made of a transparent resin such as polycarbonate. On the light exit surface of the screen 31, fine irregularities are formed, and the image light incident from the plane mirror 30 is projected.

  The plane mirror 32 is a glass substrate on which a metal such as aluminum is deposited. The plane mirror 32 bends the optical path and emits incident light to the concave mirror 33 in order to reduce the internal space of the lower housing 10.

  The concave mirror 33 is formed by, for example, depositing a metal such as aluminum on a resin such as polycarbonate to form a reflection surface. The reflection surface thus formed is a concave surface, and the image light reflected by the plane mirror 32 is enlarged to display a virtual image.

  With the above configuration, the light emitted from the red LED 12, the green LED 13, and the blue LED 14 is emitted from the cover glass 52 (FIG. 4A) onto the windshield 101 through the various components described above. As a result, the driver 110 can visually recognize a virtual image of the display image. On the other hand, when the head-up display 1 is driven, various components housed therein generate heat. In order to maintain the function of the head-up display 1, it is important how to efficiently cool these heat generating components. Therefore, a configuration for cooling the heated component in the head-up display 1 according to the present embodiment will be described.

  As shown in FIGS. 3A, 3B, and 4B, the lower housing 10 and the upper housing 50 have a duct forming wall 34 that is a convex portion for forming the duct 60, 53 is formed. By fitting (merging) the lower housing 10 and the upper housing 50, the duct forming walls 34 and 53 are brought into contact with each other, and the duct 60 that is an air passage is defined (FIG. 5). As shown in FIG. 3A, the duct 60 is formed in the head-up display 1 in a substantially J shape in plan view.

  The lower housing 10 is made of, for example, black polycarbonate, and fixes and accommodates each component described above. Similarly, the upper housing 50 is made of, for example, black polycarbonate. As shown in FIG. 4A, an opening 51 for emitting image light from the concave mirror 33 (FIG. 3A) is provided on the upper surface of the upper housing 50. As shown in FIG. The opening 51 is fitted with a plate-like cover glass 52 for preventing dust from entering. The cover glass 52 is made of, for example, transparent polycarbonate.

  Further, as shown in FIGS. 3A and 3B, an intake opening 35 is formed on the lower surface of the lower housing 10 in the drawing, and at one end of the duct 60, which is an opening for taking in air from the outside. ing. Further, as shown in FIG. 3A, an exhaust opening 36 that is a hole for discharging the air in the duct 60 to the outside is formed at the other end of the duct 60 on the side surface of the lower housing 10. ing.

  The blower 37 is an axial blower, for example, and sucks air from the axial direction and blows it in the axial direction. As shown in FIG. 3A, the air blower 37 is positioned approximately in the middle between the intake opening 35 and the exhaust opening 36 in the duct 60. When the air blower 37 is activated, air is taken from the intake opening 35, passes through the duct 60, and is discharged from the exhaust opening 36. In addition, the arrow in a figure has shown the flow of the air by the air blower 37 act | operating. By positioning the blower 37 in the duct 60 that is substantially in the middle between the intake opening 35 and the exhaust opening 36, the operation sound of the blower 37 is less likely to leak from the intake opening 35 and the exhaust opening 36. Thereby, the sound emitted from the head-up display 1 can be reduced, and a comfortable in-vehicle environment can be ensured. It should be noted that the blower device 37 may be installed in the vicinity of the intake opening 35 and the exhaust opening 36 so as to avoid an installation situation in which operating noise leaks directly from the opening. That is, by installing the blower device 37 at a position deeper from the intake opening 35 or the exhaust opening 36, it is possible to reduce the operating sound emitted to the outside.

  Further, as shown in FIGS. 3A and 3B, the DMD 28 is attached to a duct forming wall 34 in the vicinity of the intake opening 35. A DMD exposure hole 38 that is a hole for exposing the rear side of the DMD 28 to the duct 60 is formed in the duct forming wall 34 to which the DMD 28 is attached. Further, as shown in FIG. 3A, the metal circuit board 11 is attached to a duct forming wall 34 in the vicinity of the exhaust opening 36. Note that a metal circuit board exposure hole 39 that is a hole for exposing the back side of the metal circuit board 11 to the duct 60 is formed in the duct forming wall 34 to which the metal circuit board 11 is attached. As described above, by forming the exposure hole at the mounting position of the DMD 28 and the metal circuit board 11, it is possible to dissipate heat generated in the DMD 28 and the metal circuit board 11 into the duct 60. In particular, the DMD 28 is liable to cause pixel defects in a high temperature environment. Therefore, it is considered that the DMD 28 can be efficiently cooled by being provided in the vicinity of the intake opening 35 through which low-temperature outside air is taken.

  Thus, by providing the air blower 37 in the middle part of the duct 60, the operation sound of the air blower 37 is less likely to leak from the intake opening 35 and the exhaust opening 36. Therefore, it is possible to reduce noise generated from the head-up display 1.

  In the head-up display 1 according to the present embodiment, the intake opening 35, the DMD exposure hole 38, the metal circuit board exposure hole 39, the blower 37, and the exhaust opening 36 are connected by a series of ducts. For this reason, the single air blower 37 can stably blow air to a plurality of heat generating elements to save power, and the heat generating elements can be efficiently cooled. Thus, since efficient cooling is possible, the load concerning the air blower 37 can be reduced, and the operation sound which the air blower 37 emits can be reduced by extension.

  In addition, a DMD 28 that tends to become unstable at high temperatures is disposed in the vicinity of the intake opening 35, which is an intake port for outside air, and is exposed to the duct 60. Therefore, in order to ensure stable operation of the head-up display 1, it is possible to blow the fresh air just taken into the DMD 28 where cooling is most prioritized. As a result, the heat-generating component can be efficiently cooled, and normal operation of the head-up display 1 itself can be ensured.

  Further, the duct 60 serving as an air blowing path can be formed by fitting the lower housing 10 and the upper housing 50 in which the duct forming walls 34 and 53 are formed. In this way, no new dedicated parts are required to form the duct 60. As a result, the manufacturing cost of the head-up display 1 can be reduced.

  Next, a head-up display 201 according to a second embodiment of the present invention will be described with reference to FIG. The difference from the first embodiment described above is that the LED heat sink 40 is provided on the back surface of the metal circuit board 11 and the DMD heat sink 41 is provided on the back surface of the DMD 28 and protrudes into the duct 60. is there. Since other configurations are the same as those in the above-described embodiment, the same reference numerals are used in the drawings.

  The LED heatsink heat sink 40 and the DMD heatsink heatsink 41 are made of aluminum, for example, and anodized on the surface in order to improve the radiation rate. In addition, the alumite treatment is preferably black in order to enhance the heat dissipation effect by radiation. In this manner, the anodized LED heat sink 40 and the DMD heat sink 41 radiate and radiate electric heat to the air in the duct 60. Thereby, the metal circuit board 11 and the DMD 28 can be cooled more effectively.

  The present invention is not limited to the above embodiment, and various modifications and improvements can be made. For example, it is possible to provide a dustproof filter that covers the intake opening 35. Thereby, it can reduce that the dust contained in external air reaches | attains the air blower 37. FIG. Therefore, the durability of the blower device 37 can be improved.

1,201 Head-up display 10 Lower housing 11 Metal circuit board 12 Red LED
13 Green LED
14 Blue LED
15, 16, 17 Collimator lenses 18, 19 Dichroic mirrors 20, 24, 30, 32 Plane mirror 21 Condenser lens 22 Light tunnel 23 First relay lens 25 Second relay lens 26 Prism 27 Projection lens device 28 DMD
29 Internal heater 31 Screen 33 Concave mirror 34, 53 Duct forming wall 35 Intake opening 36 Exhaust opening 37 Blower 38 DMD exposure hole 39 Metal circuit board exposure hole 40 LED heat sink 41 DMD heat sink 50 Upper housing 51 Open 52 Cover Glass 60 Duct 100 Vehicle 101 Windshield 102 Dashboard 110 Driver 120 Virtual image

Claims (6)

A housing in which an intake opening for taking air into the interior and an exhaust opening for discharging the taken-in air to the outside are formed, and a duct that is a passage for the air is formed inside;
A plurality of heat generating components housed in the housing;
A blower that takes in and discharges the air,
The plurality of heat generating components are attached in an exposed state in the duct by an opening opened in a wall body defining the duct,
The head-up display, wherein the blower is installed in the duct that forms a passage of the air from the intake opening to the exhaust opening.   The head-up display according to claim 1, wherein the blower is disposed at a substantially middle point between the intake opening and the exhaust opening.   The plurality of heat generating components include: a light modulation device disposed at a position closer to the intake opening than the exhaust opening; and a light source device disposed at a position closer to the exhaust opening than the intake opening. The head-up display according to claim 1 or 2.   The head-up display according to any one of claims 1 to 3, further comprising a dustproof filter that covers the intake opening. The case is composed of a first case and a second case,
5. The duct is formed by combining the first housing and the second housing formed with the wall bodies defining the duct, respectively. 6. The head-up display according to item 1.   The head-up display according to claim 1, wherein a heat sink protruding into the duct is attached to the heat generating component.

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