JP2678818B2 - LCD projector - Google Patents

Description

TECHNICAL FIELD The present invention relates to a liquid crystal projector. [Prior Art] A liquid crystal projector displays an image using a transmissive liquid crystal display panel, and projects a display image of the liquid crystal display panel on a screen surface by a projection lens. It has become a structure. That is, FIG. 12 shows the principle of a liquid crystal projector. In the figure, 1 is a case of the projector, and a projection lens 2 formed by combining a plurality of optical lenses is provided on the front surface of the case 1. There is. 3 is a transmissive dot matrix liquid crystal display panel provided in the case 1;
Is a light source device that is provided in the case 1 so as to be positioned behind the liquid crystal display panel 3, and the light source device 4 reflects the light source lamp 5 and the illumination light from the light source lamp 5 toward the liquid crystal display panel 3. It consists of a reflector 6 and
The illumination light from the light source device 4 is incident on the liquid crystal display panel 3, and the light transmitted through the liquid crystal display panel 3, that is, the display image on the liquid crystal display panel 3 is a condensing lens (Fresnel lens in the figure).
It is condensed on the projection lens 2 by 7 and enlarged by the projection lens 2, and is projected on the screen S surface arranged in front of the projector. In other words, this liquid crystal projector enlarges the display image of the liquid crystal display panel and projects it on the screen surface.
According to this liquid crystal projector, a display image of a liquid crystal display panel having a small display screen can be greatly enlarged and viewed. [Problems to be Solved by the Invention] However, in the above liquid crystal projector, the temperature inside the case 1 is raised by the heat radiated from the light source device 4 to the periphery thereof, and the liquid crystal display panel 3 is heated. The temperature of the liquid crystal in the panel 3 rises, and due to the influence, the display contrast of the liquid crystal display panel 3 is lowered, and it becomes impossible to project a clear image on the screen S surface.
There is a problem that the life of the liquid crystal in the liquid crystal display panel 3 is shortened. It should be noted that the temperature rise in the case 1 can be suppressed by cooling the inside of the case 1 by ventilation in the case 1, but the liquid crystal projector has a sufficient structure not only for the light source but also for the liquid crystal display panel due to its structure. If it is not cooled, a good image cannot be displayed on the liquid crystal display panel, and it is difficult to efficiently cool both of them. The present invention has been made in view of the above situation, and an object thereof is to suppress a temperature rise of a liquid crystal display panel due to radiant heat from a light source device,
It is an object of the present invention to provide a liquid crystal projector capable of preventing a decrease in display contrast and a decrease in the life of a liquid crystal. [Means for Solving the Problem] The present invention provides a case, a light source, a liquid crystal display panel,
In a liquid crystal projector including a projection lens, which allows light from the light source to enter the liquid crystal display panel and which is projected by the projection lens, ventilation provided on one side of the case and the other side opposite to the one side. A hole, a cooling fan disposed near one of the ventilation holes and at substantially the same distance from the light source and the liquid crystal display panel, and the liquid crystal display panel. The liquid crystal display panel is provided with a predetermined space on one surface side, and at least a portion corresponding to the liquid crystal display panel which forms a passage through which an air flow by the cooling fan flows is configured to transmit light. It is characterized by having a wind control wall. [Operation] That is, the liquid crystal projector of the present invention is provided with ventilation holes respectively provided on one surface side of the case and the other surface side opposite to the one surface side, and in the vicinity of either one of the ventilation holes, the light source and the liquid crystal. A cooling fan for cooling the light source and the liquid crystal display panel, which are arranged at substantially the same distance from the display panel, and a gap provided on one surface side of the liquid crystal display panel with the liquid crystal display panel at a predetermined interval. Since at least a portion corresponding to the liquid crystal display panel forming a passage through which the air flow by the cooling fan is formed is provided with a wind control wall configured to transmit light, not only the light source but also the liquid crystal The display panel can also be efficiently cooled, and a good image can be displayed on the liquid crystal display panel. [Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 11. First, the overall configuration of the liquid crystal projector will be described. In FIGS. 1 and 2, reference numeral 10 denotes a projector case, and a front surface of the projector case 10 includes a plurality of lenses (not shown) in a lens barrel. Projection lens 20 with
Is provided. Then, in the case 10, the display device 30 is provided on the front side thereof and the light source device 50 is provided on the rear side thereof. The light source device 50 and the display device are provided.
Between 30 and 30, a Fresnel lens 21 that compresses the luminous flux of the illumination light from the light source device 50 to increase the brightness of the illumination light, and the illumination light that has passed through this luminous flux compression Fresnel lens 21 as the optical axis O of the projector. A light flux correcting Fresnel lens 22 that corrects the light into parallel parallel light and makes it incident on the transmissive liquid crystal display panel 43 of the display device 30 is provided, and further, on the front side of the display device 30 (the projection lens 20 side), The light transmitted through the transmissive liquid crystal display panel 43, that is, the display image of the liquid crystal display panel 43 is projected by a projection lens.
A converging Fresnel lens 23 for condensing on 20 is provided. The Fresnel lens 21 for light flux compression is a light source device.
Fresnel lens for light flux correction 22 that is placed close to 50
Are arranged close to the back surface of the display device 30, and the concentrating circular Fresnel lens 23 is arranged close to the front surface of the display device 30. 3 to 5 show the display device 30. The display device 30 comprises a display panel cooler 31 and a display unit 40 attached to one surface of the display panel cooler 31. There is. The display panel cooler 31 has a liquid crystal display panel 43 on both sides.
In a thin box-shaped cooler in which a transparent portion having a larger area than the display area 43a (see FIG. 6) is filled with a transparent cooling liquid 36 of an ethylene glycol aqueous solution cylinder, the cooling container is a liquid crystal. A frame body having an outer shape sufficiently larger than the display panel 43
The hermetically sealed structure is composed of 32 and transparent plates (glass plate, acrylic resin plate, etc.) 34 and 35 that close both sides of the frame 32. The frame 32 has a liquid crystal display panel 43 on one surface thereof.
The display unit mounting plate 32a having a window 33 having a slightly larger area than the display area 43a is formed, and the transparent plate 34 closing one surface of the frame 32 is the window 33.
The transparent plate 35 that is sized to cover the display unit mounting plate 32a and closes the other surface of the frame body 32 has substantially the same size as the outer shape of the frame body 32 and is attached to the other surface of the frame body 32. It is glued. Further, 37 is a heat pipe inserted into the cooler of the display panel cooler 30 while avoiding the portion corresponding to the window 33, and the heat pipe 37 has its both ends outside from both sides of the cooling container. It is inserted in the upper part of the cooling container in a state of protruding. The heat pipe 37 releases the heat absorbed by the cooling liquid 36 in the display panel cooler 31 to the outside of the cooler 31, and the center portion of the heat pipe 37 inserted into the cooler has a heat absorbing portion a. Both end portions projecting outside the cooling container are heat radiating parts b, b, and vertical strip-shaped large area heat radiating fins 38, 38 are provided on the outer periphery of the heat radiating parts b, b. . This heat pipe 37 is one in which a volatile working fluid (heat transfer medium) is enclosed in a metal pipe whose both ends are closed. The inner surface of the heat pipe 37 is filled with the working fluid in the heat pipe 37. An asbestos-like wick 37a that leads from the heat radiating portion b side to the heat absorbing portion a side by the capillary phenomenon is formed. The working fluid transfers heat by reversible two-phase change of evaporation / condensation. As the working fluid, for example, a fluid having a high latent heat coefficient and high permeability such as CFC is used. This working fluid is a heat pipe 37
In the heat absorption part a of the display panel cooler 31, the heat is exchanged with the cooling liquid 36 in the display panel cooler 31 to evaporate and evaporate to become vapor and rise in the heat pipe 37, and at the heat radiation part b of the heat pipe 37 to the outside. It is condensed and liquefied by the heat radiation of the wick 37a.
Permeate into the heat-absorbing portion a by the capillary phenomenon. The heat pipe 37 is configured so that the working fluid evaporated in the heat absorbing portion a is radiated from the heat radiating portions b and b at both ends of the heat pipe.
In order to guide the working fluid, which is liquefied in the heat radiating parts b and b and has permeated into the wick 37a, to the heat absorbing part a again, it is bent to a shape in which the central part is lowest and both end sides are inclined obliquely upward. There is. On the other hand, the display unit 40 attached to one surface of the display panel cooler 31 has a liquid crystal display panel in an extremely thin case-shaped housing 41 in which translucent windows 42a and 42b corresponding to the liquid display panel 43 are provided on both surfaces. The display unit 40 has a structure in which the display unit 40 and the display drive circuit board 44 are housed. That is, in FIGS. 6 to 8, 41a and 41b are a pair of metal cases that form the housing 41, and openings are formed in the both metal cases 41a and 41b to be the light transmitting windows 42a and 42b. Has been done. Among the transparent windows 42a, 42b, the transparent window 42a on the cooler mounting surface side is sized to allow the transparent plate 34 adhered to the display unit mounting plate 32a of the display panel cooler 31 to enter, and the transparent window on the opposite side. The light window 42b has substantially the same size as the display area 45a of the liquid crystal display panel 43. The display drive circuit board 44 has a shape in which an opening 44a having substantially the same size as the transparent window 42a on the cooler mounting surface side of the housing 41 is formed in the central portion thereof,
This circuit board 44 has a large number of display driving LSI chips 45, 45.
Are arranged so as to surround the opening 44a. These LSI
The chips 45, 45 are attached to the circuit board 44 by soldering their electrodes to wiring (not shown) on the surface of the circuit board 44. The circuit board 44 is adhesively fixed to the inner surface of the metal case 41a on the cooler mounting surface side of the housing 41 by a double-sided adhesive sheet (not shown). The liquid crystal display panel 43 is a transmissive dot matrix liquid crystal display panel that displays a television image.
43 is connected to a large number of display panel connection terminals (not shown) arranged in an outer peripheral edge of the circuit board 44 by sheet-shaped flexible connectors 46, 46. The liquid crystal display panel 43 is arranged in the housing 41 so as to face the translucent windows 42a and 42b on both sides thereof. The liquid crystal display panel 43 is formed by a frame-shaped double-sided adhesive sheet (not shown) in the housing. It is adhesively fixed to the inner surface of 41. This display unit 40 has a liquid crystal display panel 43 inside.
Is brought into contact with the cooler 31 by bringing it into contact with the transparent plate 34 adhered to the display unit mounting plate 32a of the display panel cooler 31, and is fixed to the cooler 31 by the fixing screws 47, 47. It is fixed to. The display device 30 in which the display unit 40 is attached to the display panel cooler 31 is shown in FIG. 1 with the liquid crystal unit 40 side facing the projection lens 20 side and the cooler 31 side facing the light source device 50 side. As shown in FIG. 2, a mounting plate 48, which is arranged in the projector case 10 and is formed by cutting and raising the housing 41 of the display unit 40, is fixed to the inside of the projector case 10 by screwing it to the inner bottom surface of the projector case 10. ing. In FIG. 2, 49a is a linear circuit unit for processing television radio waves received by an antenna unit and a tuner (not shown) provided in the projector case 10 and outputting an image signal, and 49b is the linear circuit unit. The image display control circuit unit is connected to the circuit unit 49a, and the display drive circuit board 44 in the display unit 40 is connected to the image display control circuit unit 49b by a connection cable (not shown). Next, the light source device 50 will be described. FIG. 9 to FIG. 11 show the light source device 50, in which 51 is a rectangular box-shaped light source box made of a metal plate having a circular opening 51a formed on the front surface. Yes, in this light source box 51, a light source lamp 52,
A reflector 53 that reflects the illumination light from the light source lamp 52 toward the display device 30 is provided. The reflector 53 is a parabolic mirror reflector that reflects the illumination light from the light source lamp 52 as parallel light parallel to the optical axis. The reflector 53 has an open surface facing the opening 51a on the front surface of the light source box. Then, it is fixed in the light source box 51 by means such as screwing. Also, the light source lamp 52
As a high voltage arc lamp such as a xenon lamp with high emission brightness is used as
52 is a ceramic adhesive that is inserted into the neck portion 53a of the reflector 53 and is filled with ceramic adhesive 54
It is fixed by. Note that 52b and 52b are terminal portions projecting at both ends of the high-voltage arc lamp 52, and the terminal portions 52b and 52b are connected to power supply connection terminals provided on the outer surface of the light source box 51 by lead wires (not shown). Has been done. Further, outside the neck portion 53a of the reflector 53, it is positioned obliquely above the light emitting portion 52a of the high voltage arc lamp 52 to stabilize the direction of the arc generated between the electrodes of the high voltage arc lamp 52. A magnet 55 is provided, and the arc stabilizing magnet 55 has a base portion which is a neck portion of the reflector 53.
It is fixed to the tip of a magnet supporting member 55a made of a metal plate which is inserted through 53a and fixed by the ceramic adhesive 54. Further, reference numeral 56 denotes a square tube-shaped explosion-proof cylinder made of a metal plate attached to the front surface of the light source box 51 so as to project forward thereof, and the front end of the explosion-proof cylinder 56 has an opening of the explosion-proof cylinder 56. A transparent explosion-proof glass 57 is attached to cover the surface.
This explosion-proof glass 57 is fitted to the front end of the explosion-proof cylinder 56,
The explosion-proof cylinder 56 is sandwiched and fixed by bent pieces 58 formed on both side surfaces. The explosion-proof cylinder 57 and the explosion-proof glass 57 are device parts (the Fresnel lenses 21, 22 and the display device 30 and a circuit in the projector) inside the projector due to scattered fragments (glass fragments) when the high voltage arc lamp 52 bursts due to abnormal overheating. The tempered glass 57 is, for example, chemically strengthened blue glass having a thickness of about 5 mm. Also, the light source box
Intake ports 59 and 60 are provided on the lower surface of the explosion-proof tube 56 and the explosion-proof tube 56, and the light source box 51 and the explosion-proof tube 56 are communicated with each other outside the reflector 53 at the four corners of the front surface of the light source box 51. Ventilation holes 61, 61 are provided, and exhaust holes 62, 62 are formed on the upper surface of the explosion-proof cylinder 56. The intake ports 59, 60, the ventilation holes 61, 61, and the exhaust ports 62, 62 are provided for air-cooling the light source device 50, and are cooled in the light source box 51 through the intake port 59 on the lower surface thereof. The air passes through the inside of the light source box 51 to cool the reflector 53 from its outer surface side, as shown by the arrow in FIG. 9, and the ventilation holes 61, 61 on the front surface of the light source box enter the explosion-proof cylinder 56 to exhaust the upper surface thereof. The cooling air discharged from the holes 62 and 62 and taken into the explosion-proof cylinder 56 through the intake port 60 on the lower surface thereof cools the reflector 53 and the explosion-proof glass 57 from the inner surface side thereof, and the exhaust holes are formed.
Emitted from 62,62. The light source device 50 is installed in the rear part of the projector case 10 as shown in FIGS. 1 and 2.
It is connected by a power supply unit 63 provided on the side of the power supply unit and a power supply cable 64. In addition, this power cable 64 is
It is connected to the above-mentioned power supply connection terminal provided on the outer surface of the light source box 51. Further, the light source device 50,
When the high voltage arc lamp 52 bursts, the light source box 51 and the explosion-proof tube 56 are replaced as a whole, and therefore the light source device 50 is detachably fixed in the projector case 10 by means such as screwing. ing. On the other hand, in FIG. 1 and FIG. 2, 70 is a heat insulating wall provided in the projector case 10.
The display device 30 inside the case 10 near the display device 30.
Side and the light source device 50 side, it is composed of a vertical wall portion, and an upper wall portion extending from the upper end of the vertical wall portion to near the light source device 50. The vertical wall portion is illuminated by the light source device 50. An opening 71 through which light passes is provided. Further, in the projector case 10, a lower partition wall 11a is provided upright from the bottom surface of the case in the vicinity of the front surface of the display unit of the display device 30.
And an upper partition wall 11b hanging from the upper surface of the case. The lower partition wall 11a is a frame-shaped one that also serves as a support frame for the light-collecting Fresnel lens 23 arranged on the front side of the display device 30.
23 is adhered and fixed to the lower partition wall 11a. Further, the upper partition wall 11b is formed at a height such that its lower end is close to or in contact with the upper edge of the light collecting Fresnel lens 23, and the upper partition wall 11b and the light collecting Fresnel lens 23 and the lower partition are formed. A wind control wall for allowing the cooling air to flow along the front surface of the display unit 40 by the wall 11a.
11 are configured. Further, on the lower surface of the projector case 10, the arrangement portion of the light source device 50, the portion between the light source device 50 and the display device 30, the arrangement portion of the display device 30, and the portion in front of the wind control wall 11. In addition, the intake holes 12a, 12b, 12c, 12d are provided respectively, and in the lower part of the wind control wall 11 (the part below the converging Fresnel lens 23 of the lower partition wall 11a), The air taken in from the front air intake hole 12d is supplied to the wind control wall 11 and the display unit 4
A ventilation hole 13 is provided to be introduced into the air passage between 0 and. Further, a blower fan 73, which is located above the upper wall portion of the heat insulating wall 70 and is rotated by a motor 72, is provided on the upper portion of the projector case 10, and an exhaust gas is provided on the upper surface of the projector case 10 in this portion. Holes 14, 14 are provided. The blower fan 73 is for sucking outside air into the projector case 10 through the intake holes 12a, 12b, 12c, 12d as shown by an arrow in FIG. 1 to cool the inside of the projector by air. The cooled air taken in is the light source device 5
The cooling air that has passed through 0 to cool the light source device 50 and that has been taken in through the air intake holes 12b passes between the light source device 50 and the display device 30 to lower the temperature inside the case between them and to Fresnel lens 21 for light flux compression. And the Fresnel lens 22 for light flux correction is cooled. Further, the cooling air taken in through the intake holes 12c cools the display device 30 from the outside and also cools the cooling liquid 36 in the display panel cooler 31 by exchanging heat with the heat pipe 37. Further, the cooling air taken in through the intake holes 12d is introduced between the wind control wall 11 and the display unit 40 through the ventilation hole 13 provided in the lower portion of the wind control wall 11, and the display unit 40 is cooled from the front side thereof. At the same time, the condenser Fresnel lens 23 is also cooled. The air that has cooled each of these parts is exhausted to the outside of the case 10 through the exhaust holes 14, 14. It should be noted that the light source device 50 and the display device 3 are taken in from the intake hole 12b.
The air that has passed between 0 and 0 bypasses the tip of the upper wall of the heat insulating wall 70 and both sides, and is exhausted from the exhaust holes 14, 14. Further, in FIG. 1 and FIG. 2, 15 and 16 are the blower fans 73.
The wind guide wall 15 on the light source device 50 side is a straight wall along the width direction of the case, and the wind guide wall 16 on the display device 30 side is a semicircular wall. Therefore, in this liquid crystal projector, the transparent cooling liquid 36 is filled in a container in which a transparent area having a larger area than the display area of the liquid crystal display panel 43 is formed on both sides, and the heat absorbed by the cooling liquid 36 is stored in the container. Heat pipe that releases heat to the outside
The display unit 40 accommodating the liquid crystal display panel 43 and its display drive circuit board 44 is attached to one surface of the display panel cooler 31 in which the 37 is inserted, and the liquid crystal display panel 43 is attached to the other surface side of the display unit 40. A wind control wall 11 in which a converging Fresnel lens 23 is provided in a portion facing
Is provided in close proximity to the display unit 40, and a passage for cooling air blown by the blower fan 73 is formed between the wind control wall and the display unit 40.
A rise in temperature of the liquid crystal display panel 43 due to radiant heat from 50 can be suppressed to a low level to prevent a decrease in display contrast and a decrease in the life of the liquid crystal. That is, in the liquid crystal projector of the above-described embodiment, the inside thereof is air-cooled, and the heat insulating wall 70 is provided on the side of the display device 30 facing the light source device 50. Therefore, the display device 30 is radiated from the light source device 50. Can be prevented to some extent from being heated, but even with this, the light source device
Radiant heat from the heat insulating wall 70 and the heat insulating wall 70
The liquid crystal display panel 43 in the display device 30 will rise in temperature by leaking from the surroundings to the display device 30 side. Therefore, in this liquid crystal projector, the display unit 40 provided with the liquid display panel 43 is provided on one surface of the display panel cooler 31, and the display unit 40 is cooled by the cooling liquid 36 in the display panel cooler 31. A wind control wall 11 for allowing cooling air to flow to the other surface side of the display unit 40 along the front surface of the display unit 40 to flow to the other surface side of the display unit 40.
By providing the cooling air blown by the blower fan 73 along the surface of the display unit 40, the liquid crystal display panel is also cooled by this cooling air. Since the cooling liquid 36 exchanges heat with the heat pipes 37, 37 while convection in the cooling device 31, the heat absorbed by the cooling liquid 36 is released to the outside by the heat pipes 37, 37, and the display panel cooling device 31 The cooling efficiency of the display unit 40 by means of can always be kept high, and the cooling air flowing through the air passage between the display unit 40 and the wind control wall 11 flows at a high flow velocity because of this narrow passage, The display unit 40 can also be efficiently cooled by the air flow. Therefore, according to this liquid crystal projector, it is possible to cool the liquid crystal display panel in the display unit 40 from both sides thereof and suppress the temperature rise of the liquid crystal display panel 43 due to the radiant heat from the light source device 50. It is possible to prevent a decrease in contrast and a decrease in the life of the liquid crystal. Incidentally, the display panel cooler 31 is one in which a transparent cooling liquid 36 is filled in a container in which a transparent area having a larger area than the display area of the liquid crystal display panel 45 is formed on both sides, and the wind control wall 11 also, Since the portion facing the liquid crystal display panel 43 is transparent, the light passing through the liquid crystal display panel 45 is not blocked by the display panel cooler 31 and the wind control wall 11. In the above embodiment, the liquid crystal display panel 43 is housed in the housing 41 together with the display drive circuit board 44, and the display unit 40 is attached to the display panel cooler 31. Instead, it may be attached to the display panel cooler 31 alone. Further, in the above-mentioned embodiment, the transparent portion of the wind control wall 11 provided in close proximity to the other surface of the liquid crystal display panel 43 and facing the liquid crystal display panel 43 is constituted by the converging Fresnel lens 23. The Fresnel lens 23 for collecting holes may be provided separately from the wind control wall 11,
In that case, the part of the wind control wall 11 facing the liquid crystal display panel 43 is formed of a transparent plate such as a glass plate, or
11 It is sufficient to configure the whole with a transparent plate. [Advantages of the Invention] The liquid crystal projector of the present invention is provided with ventilation holes respectively provided on one surface side of the case and the other surface side opposite to the one surface side, in the vicinity of any one of the ventilation holes, and the light source and the liquid crystal. A cooling fan for cooling the light source and the liquid crystal display panel, which are arranged at substantially the same distance from the display panel, and a gap provided on one surface side of the liquid crystal display panel with the liquid crystal display panel at a predetermined interval. Since at least a portion corresponding to the liquid crystal display panel forming a passage for allowing the air flow by the cooling fan to flow is provided with a wind control wall configured to transmit light, not only the light source but also the liquid crystal The display panel can also be efficiently cooled, a good image can be displayed on the liquid crystal display panel, and ventilation holes are provided on one side of the case and the other side opposite to this one side. Since each is provided, the resistance of the air flow can be reduced, the cooling fan can be downsized, and the noise can be reduced.

BRIEF DESCRIPTION OF THE DRAWINGS FIGS. 1 to 11 show an embodiment of the present invention.
1 and 2 are a vertical sectional front view and a partially cutaway plan view of a liquid crystal projector, FIG. 3, FIG. 4 and FIG. 5 are a front view, a plan view and a vertical sectional side view of a display device, and FIG. A partially cutaway front view of the display unit, FIGS. 7 and 8 are enlarged sectional views taken along the lines VII-VII and VIII-VIII of FIG. 6, and FIGS. 9, 10 and 11 are light source devices. FIG. 5 is a vertical front view, a partially cut plan view and a partially cut side view of FIG. Twelfth
The figure is a principle configuration diagram of a conventional liquid crystal projector. 10 …… Projector case, 11 …… Wind control wall, 20 …… Projection lens, 23 …… Converging Fresnel lens, 30 …… Display device, 31 …… Display panel cooler, 34,35 …… Transparent plate, 36 ...
… Coolant, 37 …… Heat pipe, 40 …… Display unit,
41 …… housing, 42a, 42b …… transparent window, 43 …… liquid crystal display panel, 73 …… blower fan.

Continuation of front page    (56) References JP-A-58-85736 (JP, A)                 JP-A-52-77699 (JP, A)                 Actual development Sho 61-140345 (JP, U)                 Actual public Sho 39-32971 (JP, Y1)

Claims (1)

(57) [Claims] A liquid crystal projector, comprising: a case, a light source, a liquid crystal display panel, and a projection lens, wherein the light of the light source is incident on the liquid crystal display panel and projected by the projection lens, the one surface side of the case and the one surface thereof. Side and the ventilation hole provided on the other surface side facing each other, and arranged in the vicinity of any one of the ventilation holes and at substantially the same distance from the light source and the liquid crystal display panel, the light source and the liquid crystal display panel A cooling fan for cooling the liquid crystal display panel, and a liquid crystal display panel provided on one side of the liquid crystal display panel with a predetermined space therebetween, and a passage through which an air flow by the cooling fan flows is formed in the space. A liquid crystal projector comprising: a wind control wall configured to transmit light in a portion corresponding to the liquid crystal display panel.