JP2008058654A - Projection side optical system and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve the problem that if a high performance doublet used in an imaging optical system is used in the projection optical system of a projector, the temperature of each lens increases in the projection side optical system of the projector during image projection, and if the projector is repeatedly used, the doublet using different materials of different thermal expansion coefficients may suffer from displacement or separation of a cemented face. <P>SOLUTION: The projection side optical system 90 has a lens barrel 91. The lens barrel 91 stores and fixes a plurality of lenses 93 including the doublet 155, wherein the fixed part of the doublet 155 is used as a heat conductive lens barrel part 151 formed from a thermal conductor. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projection-side optical system for a projector and a projector equipped with the projection-side optical system.

  2. Description of the Related Art Today, data projectors that project an image displayed on a personal computer screen, an image of a video signal, an image based on image data stored in a memory card or the like onto a screen are widely used.

  In many cases, this data projector uses a small high-intensity light source such as a metal highland lamp or an ultra-high pressure mercury lamp, and the light emitted from the light source is converted into light of three primary colors by a color filter. It is structured to irradiate a display element called DMD (Digital Micro Device) and project the transmitted light or reflected light of the display element onto a screen through a lens group which is a projection side optical system having a zoom function. Yes.

  This data projector incorporates a plurality of heat sources such as a light source, a light source side optical system, a power supply circuit, and a display element, and the light source is heated to nearly 1000 degrees. For this reason, a mechanism for cooling the light source device, the power supply circuit, and the like, which are heat sources by providing an air cooling fan, is incorporated.

  As such a cooling mechanism, a cooling air flow path is formed so as to distinguish a light source device that has a particularly high temperature and a large amount of heat generation from other heat generation sources, and cooling air that cools an optical system at a temperature lower than that of the light source device. There has been proposed one that cools a light source and cools it with cooling air in which a power source unit or the like has a flow path different from that of the light source.

  For example, in Japanese Patent Application Laid-Open No. 2005-173020 (Patent Document 1), a plurality of cooling fans are used to cool a heat source of each partition flow path by providing a substrate and partition walls for creating an air flow in a housing. Air inside the housing is exchanged with outside air through the exhaust holes and intake holes.

  The light source is heated from several hundred degrees to nearly 1000 degrees, and a heat absorption filter is used for the light source device. The lens of the optical system unit that transmits the light bundle from the light source device is Since the temperature rises by being warmed by the light beam, the image may fluctuate or the focus may be shifted. Therefore, cooling is performed by the outside air taken into the projector housing.

  Further, the light source side optical system and the projection side optical system are made to be L-shaped by crossing the optical axis of the light source side optical system and the optical axis of the projection side optical system so that the exhaust heat from the light source is not transmitted to the projection side optical system. Many of them are arranged to increase the distance between the light source and the projection-side optical system (for example, Patent Document 2).

  Further, in JP-A-2001-174920 (Patent Document 2), an intake fan is disposed in the vicinity of the projection port, an exhaust fan is disposed in the vicinity of the light source device, and an air flow path is formed between them. Thus, there has been proposed a cooling mechanism for a projection apparatus in which various optical systems are cooled with low-temperature air sucked from an intake fan and then the light source device is cooled.

Further, in today's photographing optical system, a bonded lens is used as a high-performance lens that is small and has little aberration (for example, Patent Document 3).
This bonded lens has a lens performance of an aspherical lens by bonding an optical resin lens to an optical glass lens.
JP 2005-173020 A Japanese Patent Laid-Open No. 2001-174920 Japanese Patent Laid-Open No. 2001-100092

  In recent years, it has been demanded that high-definition images can be projected along with miniaturization of projectors, and attempts have been made to use a bonding lens used in an imaging optical system for a projection optical system of a projector.

  However, in the projection-side optical system of a projector, when the temperature of each lens rises during the projection of an image and the projector is used repeatedly, with a bonded lens using different materials with different thermal expansion coefficients, There was a risk that the surface may be displaced or peeled off.

  In order to solve such a problem, the present invention provides a projection-side optical system that suppresses the temperature rise of the lens.

  The present invention provides a lens barrel in which a plurality of lenses including a bonded lens (155) are housed and fixed in a lens barrel, and the fixing portion of the bonded lens (155) is a heat conducting lens barrel (151) made of a good thermal conductor. A projection-side optical system (90).

The heat good conductor may be a metal such as an aluminum alloy or a copper alloy, and a heat radiating fin (153) may be provided on the outer periphery of the heat conducting lens barrel (151).
It is preferable that the outer periphery of the lens having a high coefficient of thermal expansion in the bonded lens (155) is closely fixed to the heat conducting lens barrel (151).

  The projector (10) according to the present invention uses a bonding lens (155) for the lens group of the projection-side optical system (90), and the lens barrel for fixing the bonding lens (155) is a bonding lens. The heat conducting lens barrel (151) is formed in the (155) portion.

  Since the projection-side optical system according to the present invention includes the heat conducting lens barrel portion in the lens barrel, the lens rising temperature is dissipated through the heat conducting lens barrel portion, and the temperature rise of the bonded lens is reduced. The bonded lens can be used in a projector without causing lens displacement or peeling in the bonded lens.

  In addition, a projector incorporating a projection-side optical system using a bonding lens can project a beautiful image with a small size.

  The projector 10 according to the best mode for carrying out the present invention is composed of a substantially rectangular parallelepiped housing. Inside the housing is a light source device 63, an optical system unit 77, and a blower as a cooling fan for cooling the light source device 63. 110.

  The optical system unit 77 includes an illumination side block 78, an image generation block 79, and a projection side block 80. The projection side optical system 90 of the projection side block 80 includes a plurality of lenses including a bonding lens 155. Is mounted and fixed in the lens barrel, and the fixing lens 155 has a lens barrel in which the heat-conducting lens portion 151 is fixed to a portion where the bonding lens 155 is fixed, and at least around the lens having a high thermal expansion coefficient in the bonding lens 155 Is a projection-side optical system 90 that is closely fixed to the heat conducting lens barrel 151.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. As shown in FIG. 1, a projector according to an embodiment of the present invention has a substantially rectangular parallelepiped shape, and includes a lens cover 19 that covers a projection port on a side of a front plate 12 that is a front side plate of a main body case. In addition, the front plate 12 is provided with a plurality of exhaust holes 17. The exhaust holes 17 prevent light in the casing from leaking to the outside and prevent exhaust heat from flowing in front of the projection port. It has the louver 20 for.

  The top plate 11 as a main body case is provided with a key / indicator section 37. The key / indicator section 37 includes a power switch key, a power indicator for notifying power on / off, and a lamp of the light source device. A key or indicator such as a lamp switch key for turning on the lamp, a lamp indicator for displaying the lighting of the lamp, an overheating indicator for notifying when the light source device or the like overheats is provided.

  Further, on the back of the main body case (not shown), a control signal from a power supply adapter plug or a remote controller, and an input / output connector part provided with a USB terminal, a D-SUB terminal for inputting image signals, an S terminal, an RCA terminal, etc. Is provided with an Ir receiving unit or the like.

  A plurality of air intake holes 18 are provided in the right side plate 14 which is a side plate of the main body case (not shown) and the left side plate 15 which is the side plate shown in FIG.

  As shown in FIG. 2, the control circuit of the projector 10 includes a control unit 38, an input / output interface 22, an image conversion unit 23, a display encoder 24, a display drive unit 26, etc. The image signals of various standards input from the unit 21 are converted so as to be unified into image signals of a predetermined format suitable for display by the image conversion unit 23 via the input / output interface 22 and the system bus (SB). Are sent to the display encoder 24.

  The display encoder 24 develops and stores the transmitted image signal in the video RAM 25, generates a video signal from the stored contents of the video RAM 25, and outputs the video signal to the display drive unit 26.

  A display drive unit 26 to which a video signal is input from the display encoder 24 drives a display element 51, which is a spatial light modulation element (SOM), at an appropriate frame rate corresponding to the image signal sent. A projection lens group that forms a light image with the reflected light of the display element 51 and makes it a projection-side optical system 90 by making light from the light source device 63 incident on the display element 51 through the light source-side optical system. The movable lens groups 96 and 98 of this projection system lens group are driven for zoom adjustment and focus adjustment by the lens motor 45.

  In addition, the image compression / decompression unit 31 performs a recording process for sequentially writing a luminance signal and a color difference signal of an image signal to a memory card 32 that is a removable recording medium by performing data compression by processing such as ADTC and Huffman coding. In the mode, the image data recorded on the memory card 32 is read out, and individual image data constituting a series of moving images is decompressed in units of one frame and sent to the display encoder 24 via the image conversion unit 23. A moving image or the like can be displayed based on the stored image data.

  The control unit 38 controls the operation of each circuit in the projector 10, and includes a ROM that stores operation programs such as a CPU and various settings fixedly, and a RAM that is used as a work memory. ing.

  Further, the operation signal of the key / indicator unit 37 composed of the main key and the indicator provided on the upper surface plate 11 of the main body case is directly sent to the control unit 38, and the key operation signal from the remote controller is received by Ir. The code signal received by the unit 35 and demodulated by the Ir processing unit 36 is sent to the control unit 38.

  An audio processing unit 47 is connected to the control unit 38 via a system bus (SB). The audio processing unit 47 includes a sound source circuit such as a PCM sound source, and converts the audio data into analog data in the projection mode and the playback mode. The speaker 48 can be driven to emit loud sounds.

  The control unit 38 controls the power supply control circuit 41. When the lamp switch key is operated, the power supply control circuit 41 turns on the lamp 64 of the light source device, and the cooling fan drive control circuit 43 Is to detect the temperature by a temperature sensor provided in the light source device or the like to control the rotation speed of the cooling fan, and to maintain the rotation of the cooling fan even after the lamp of the light source device is turned off by a timer or the like.

  These ROM, RAM, IC and circuit elements are attached to the control circuit board 103 as the main control board shown in FIG. 3, and the power system power supply control circuit 41 is incorporated in the lamp power supply circuit block 101 for control. A control circuit board 103 as a main control board of the system and a power control circuit board 102 to which the lamp power circuit block 101 of the power system is attached are formed separately.

  Further, as shown in FIG. 3, the projector 10 has an internal structure in which a power control circuit board 102 with a lamp power circuit block 101 and the like attached thereto is disposed in the vicinity of the right side plate 14, and as shown in FIG. A partition wall 120 for the inside of the body forms an airtight space chamber 121 on the back plate 13 side and an exhaust side space chamber 122 on the front plate 12 side in an airtight manner, and a sirocco fan type blower 110 is cooled in the air intake side space chamber 121 by a cooling fan. In the vicinity of the back plate 13, it is arranged on the bottom plate 16, and the discharge port 113 of the blower 110 is arranged in the exhaust side space chamber 122.

  Further, the light source device 63 is disposed in the exhaust side space 122, the optical system unit 77 is disposed along the left side plate 15, and the illumination side block 78, the image generation block 79, and the projection side block 80 are configured. The illumination side block 78 of the optical system unit 77 is in open communication with the exhaust side space chamber 122 so that a part of the optical system unit 77 is positioned in the exhaust side space chamber 122.

In the light source device 63, an ultrahigh pressure mercury lamp is provided as a discharge lamp 64 inside a reflector 65 whose front surface is covered with explosion-proof glass.
Further, as shown in FIG. 5, the optical system unit 77 is composed of three blocks: an illumination side block 78 located in the vicinity of the light source device 63, an image generation block 79, and a projection side block 80. The illumination side block 78 is provided with a first reflection mirror 72 that reflects light emitted from the light source device 63 to the color wheel 71 and color filters for red light, green light, and blue light around the wheel block 73. A color wheel 71 that is rotated and a light tunnel 75 that converts the light transmitted through the filter of the color wheel 71 into a light beam having a uniform intensity distribution are provided. Further, an illumination-side block partition wall 127 connected to the partition partition wall 120 so as to penetrate the light tunnel 75 is provided.

  The image generation block 79 includes a second reflection mirror 74 that changes the direction of the light emitted from the light tunnel 75 by 90 degrees, and a plurality of sheets that collect the light reflected by the second reflection mirror 74 on the display element 51. A light source side lens group 83 formed of the above lens, an irradiation mirror 84 for irradiating the light transmitted through the light source side lens group 83 to the display element 51 at a predetermined angle, and the DMD (digital Micromirror device), a display element unit for holding the display element 51, and the like.

  Further, the projection-side block 80 incorporates a lens group of the projection-side optical system 90 that emits light that is reflected by the display element 51 and forms an image to the screen. The projection-side optical system 90 includes a fixed lens barrel. A variable lens having a zoom function, comprising a fixed lens group 93 built in 91 and a first movable lens group 96 and a second movable lens group 98 built in the first movable lens barrel 95 and the second movable lens barrel 97. In this embodiment, the first movable lens group 96 and the second movable lens group 98 are moved by a lens motor to enable zoom adjustment and focus adjustment.

  Further, an optical system control board 86 for controlling zoom and focus adjustment of the projection side optical system 90 is disposed between the optical system unit 77 and the left side plate 15, and this optical system control board 86 is the first and By controlling the operations of the second movable lens barrels 95 and 97 and the first and second movable lens groups 96 and 98, the zoom function and focus adjustment can be performed.

  In addition, the illumination side block 78 and the projection side block 80 are arranged adjacent to each other so as to form a gap 128 so as to have a cooling air flow path between both blocks. Has an outer wall. The image generation block 79 connects the illumination side block 78 and the projection side block 80, and the optical system unit 77 has the optical axis of the illumination side block 78 and the optical axis of the projection side block 80 parallel to each other as a whole. It has a shape of the shape. Further, the outer wall of the illumination-side block 78 that is at a high temperature of the optical system unit 77 is formed using a heat insulating member having a low thermal conductivity such as a resin in order to reduce heat conduction.

In some cases, the outer wall of the illumination side block 78 is formed using a metal that is light in weight and high in heat conduction, such as aluminum, and the heat of the illumination side block 78 is radiated to the outside.
In addition, the partition wall 127 of the illumination side block 78 has a cutout 129 serving as an air flow path in the upper part near the light tunnel 75.

  The lens group as the projection-side optical system 90 incorporated in the projection-side block 80 is composed of a fixed lens group 93 and a first movable lens group 96 and a second movable lens group 98 which are movable lens groups, as shown in FIG. As shown in FIG. 6A, the on-state light beam is transmitted through the fixed lens group 93, the second movable lens group 98, and the first movable lens group 96, and the off-state light beam is projected as shown in FIG. An image is formed on the screen so as not to enter the side optical system 90.

  Further, when an image is formed on the screen by the on-state light beam, the zoom magnification is adjusted so that the first movable lens group 96 and the second movable lens group 98 are moved in the optical axis direction to adjust the size of the image displayed on the screen. In addition, the focus adjustment is performed to make the image on the screen clear.

  As shown in FIG. 6, the CCD that is the display element 51 has a front surface protected by a cover glass 55, and a condenser lens 57 is disposed in front of the cover glass 55 to irradiate the display element 51. The light from the mirror is incident on the CCD as a parallel light beam.

  The fixed lens group 93 and the movable lens groups 96 and 98 are fixed inside the lens barrel, as shown in FIG. 7, and each lens constituting the fixed lens group 93 has a stopper ring. When a lens having a different lens diameter is incorporated, the lens is fixed at a predetermined position of the fixed barrel 91 using a spacer ring 159.

  In addition, the bonded lens 155 using optical glass and optical resin is closely attached to the fixed barrel 91, and the fixed barrel 91 at the fixed portion of the bonded lens 155 is made of a metal such as an aluminum alloy or a copper alloy. The heat conducting lens barrel portion 151 is formed using a good heat conductor.

  Of the convex lens and concave lens in the bonded lens 155 that are closely fixed to the heat conducting lens barrel 151, the concave lens whose outer periphery is wide and in contact with the heat conducting lens barrel 151 has a high coefficient of thermal expansion such as optical resin. It is a lens.

  In addition, the fixed barrel 91 is formed by forming a cylindrical body made of a resin on the front or rear side of the thermal conduction barrel section 151 or on both front and rear sides thereof by insert molding using a metallic cylindrical body as the thermal conduction barrel section 151. A continuous cylindrical body made of a synthetic resin and a metal is formed into a lens barrel, and a plurality of lenses including a bonded lens 155 are built in and fixed as a fixed lens group 93.

  In the first and second movable lens groups 96 and 98, desired lenses are fixed inside the first movable lens barrel 95 and the second movable lens barrel 97, respectively. Has a small-diameter portion housed in the holding cylinder 161 and a large-diameter portion A protruding from the holding cylinder 161, and a lens is fixed to each of the small-diameter portion and the large-diameter portion A using a stopper ring 158, and the first movable The lens group 96 is used.

  The first movable lens barrel 95 has a first cam pin 167 at the small diameter portion, and the first cam pin 167 passes through the first sliding groove 163 of the holding cylinder 161 and the tip of the first cam pin 167 is positioned at the first end. This is inserted into a first cam groove 173 that is a cam groove of one cam cylinder 171.

  The first cam groove 173 is spirally formed along the periphery of the first cam cylinder 171 and the first sliding groove 163 is a groove formed linearly along the axial direction of the holding cylinder 161, By rotating the first cam cylinder 171, the first cam pin 167 is moved back and forth along the first sliding groove 163 in accordance with the spiral inclination of the first cam groove 173, and the first movable lens barrel 95, ie, the first The movable lens group 96 is moved back and forth along the optical axis.

  Each lens constituting the second movable lens group 98 is also fixed to the second movable lens barrel 97 by a stopper ring 158, and the second movable lens barrel 97 is also accommodated in the holding tube 161 in the axial direction of the holding tube 161. A second cam pin 168 that passes through a linearly formed second sliding groove 165 is provided, and the tip of the second cam pin 168 is inserted into a spiral second cam groove 177 provided in the second cam cylinder 175. Thus, the second movable barrel 97 and the second movable lens group 98 are moved back and forth along the optical axis by the rotation of the second cam barrel 175.

  In this projection-side optical system 90, a bonded lens 155 is incorporated in the fixed lens group 93, and a part of the fixed lens barrel 91, which is a lens barrel in which the outer periphery of the bonded lens 155 is closely contacted, is a heat conducting lens tube made of a good heat conductor. Although the portion 151 is a lens that supports the movable lens group, a lens that fixes the outer periphery of the movable barrel, such as the large-diameter portion A of the movable barrel, is used as a laminated lens 155. A portion of the movable lens barrel that fixes the lens 155 may be a heat conducting lens barrel portion 151.

  Further, as shown in FIGS. 8A and 8B, the portion of the lens barrel that is in close contact with the periphery of the bonded lens 155 is referred to as a heat conducting barrel portion 151. A heat radiating fin 153 may be formed on the outer periphery to increase the outer peripheral area of the heat conducting lens barrel 151 and increase the heat dissipation effect.

  The diameters of the optical glass lens and the optical resin lens used as the bonding lens 155 are not limited to the case where both lenses having the same diameter and different materials are fixed to the heat conducting lens barrel 151 as shown in FIG. As shown in (A) and (B), the diameter of the lens having a large coefficient of thermal expansion is increased, and the diameter of the lens having a large coefficient of thermal expansion is increased. The outer periphery of the lens is securely fixed to the heat conducting lens barrel 151.

  Further, the blower 110 for cooling such various heat sources has a suction port 111 in the suction side space chamber 121, and the discharge port 113 has a substantially square cross section and is connected to the partition partition 120, 120 and the exhaust side space 122 partitioned by the illumination side block partition wall 127 of the illumination side block 78 are exhausted from the blower 110, and a control circuit board is located near the suction port 111 of the blower 110. 103 is disposed.

  Further, as shown in FIG. 5, the partition wall 120 includes an intake side space chamber 121 in which a relatively low temperature device such as various optical systems and various substrates is disposed, and a high temperature such as the light source device 63. And an exhaust side space chamber 122 in which a light source unit such as a first reflection mirror 72 and a color wheel 71 arranged near the light source device 63 is arranged.

The partition wall 120 is composed of a plate-like first partition wall 123, a second partition wall 124, a third partition wall 125, and an upper surface partition wall and a lower surface partition wall (not shown).
The first partition wall 123 is connected to the end portion of the partition wall 127 included in the optical system unit 77, extends substantially in parallel with the front plate 12 from the end portion of the partition wall included in the optical system unit 77, and the discharge port of the blower 110. The power supply control circuit board 102 is separated by penetrating 113. The first partition wall 123 is a partition wall provided for exhausting exhaust from the discharge port 113 of the blower 110 completely to the exhaust side space chamber 122 side.

  Further, the second partition wall 124 is separated from the end portion of the first partition wall 123 to the end portion of the power supply control circuit board 102 substantially in parallel with the power supply control circuit board 102. The third partition 125 is separated from the end of the second partition 124 to the right side plate 14 substantially parallel to the front plate 12. The second partition wall 124 and the third partition wall 125 are partition walls provided to partition the power supply control circuit board 102 and the exhaust side space chamber 122.

  The upper partition and the lower partition are arranged so that the heat of the exhaust side space 122 is not directly transferred to the top plate 11 and the bottom plate 16, and the exhaust side space 122, the top plate 11, and the bottom plate are arranged. There is a space between 16.

  The first partition wall 123, the second partition wall 124, and the third partition wall 125 use heat insulating members such as resin as in the optical system unit 77. Thereby, it is possible to prevent the high heat generated by the light source device 63 in the exhaust side space 122 from leaking to the outside.

  Next, the flow of air in the projector 10 will be described. As shown in FIG. 5, the back plate 13 is provided with an intake hole 18 in the rear portion of the place where the display element 51 is located, and air flows between the back plate 13 and the optical system unit 77 having the display element 51. A passage is formed so that outside air sucked from the intake holes 18 provided in the back plate 13 and the intake holes 18 provided behind the left plate 15 flows along the back plate 13 in the direction of the blower 110.

  A display element heat radiating plate 53 is arranged behind the display element. The control circuit board 103 serves as two control boards between the two control circuit boards 103 or between the two control circuit boards 103. Above or below, air flowing along the control circuit board 103 is sucked into the suction port 111 of the blower 110.

  Therefore, when the fan of the blower 110 is rotated, the blower 110 serving as a cooling fan sucks the surrounding air from the suction port 111 and sucks the air around the blower 110 inside the projector 10, so that the side plate of the housing of the projector 10 The outside air can be sucked into the projector 10 through a large number of intake holes 18 provided in the projector 10.

  A part of the outside air sucked from the intake holes 18 provided in the left side plate 15 and the back plate 13 forms an air flow path between the back plate 13 and the optical system unit 77 so as to cool the display element heat radiating plate 53. The air flows along the control circuit board 103 and is sucked into the suction port 111 of the blower 110 through the upper and lower surfaces of the control circuit board 103 and the space between the control circuit boards 103. The other outside air sucked from the suction hole 18 of the left side plate 15 cools the optical system unit 77.

  In addition, some of the outside air sucked into the projector 10 from the air intake hole 18 of the right side plate 14 passes through the periphery of the lamp power circuit block 101 and the like, reaches the control circuit board 103 while cooling the power circuit board 102, and is controlled. The air flows along the circuit board 103 and is sucked into the suction port 111 of the blower 110. The remaining sucked outside air flows along the first partition wall 121 and is sucked into the suction port 111 of the blower 110.

  A part of the exhaust from the blower 110 blown into the exhaust side space 122 flows along the color wheel 71, and most of the exhaust flows around the light source device 63 that has become hot. In addition, a part of the air flowing around the light source device 63 flows from the opening provided in the reflector 65 so as to pass through the inside of the reflector 65, and the other part is in the vicinity of the first reflecting mirror 72, the color wheel 71, and the like. Then, each part of the light source unit is cooled together with the light source device 63.

  In this way, the high-temperature air after cooling the light source device 63 and the color wheel 71 in the exhaust-side space chamber 122 spreads throughout the front plate 12 and is discharged from the exhaust holes 17 provided in the front plate 12. . Since the louver 20 is attached to the exhaust hole 17, it is possible to block the internal light so as not to leak to the outside, and to reduce the exhaust temperature discharged to the outside. Since the louver 20 is attached obliquely toward the side, it is possible to prevent high-temperature exhaust from being discharged in the direction of the projection-side optical system 90.

  Further, as shown in FIG. 9, the air flow in the vicinity of the optical system unit 77 is a part of the air sucked from the suction hole 18 of the left side plate 15 between the optical system unit 77 and the bottom plate 16. And flows into the gap 128 between the illumination side block 78 and the projection side block 80 to prevent the high temperature heat of the illumination side block 78 from being transmitted to the projection side block 80. The air flowing into the gap 128 flows into the intake side space chamber 121 in the housing through the cutout 129, and further sucked into the suction port 111 of the blower 110 and exhausted into the exhaust side space chamber 122.

  According to the present embodiment, since the gap 128 serving as an air flow path is formed between the illumination side block 78 and the projection side block 80 constituting the optical system unit 77, the heat of the illumination side block 78 is transferred to the projection side block 80. The projection side block 80 becomes hot due to the heat of the illumination side block 78, and it is possible to prevent the projection image from defocusing and fluctuations in the projection image. By forming the above, the cooling effect of the optical system unit 77 can be enhanced.

  Then, fresh air from the outside taken in from the intake hole 18 of the left side plate 15 is caused to flow around the projection side optical system 90 of the projection side block 80, the lens barrel of the projection side optical system 90 is cooled, and the heat conduction mirror The temperature rise of the bonding lens 155 can be reduced by the tube portion 151, and the entire projector 10 capable of projecting a high-definition image can be reduced in size by using the bonding lens 155 as a small optical unit 77. It can be done easily.

  The present invention is not limited to the above-described embodiments, and can be freely changed and improved without departing from the gist of the invention. The cooling fan is not limited to the sirocco fan type blower 110.

1 is a perspective view of a projector according to an embodiment of the invention. FIG. 3 is a control block diagram of the projector according to the embodiment of the invention. FIG. 3 is a perspective view of the projector according to the embodiment of the present invention with a part of the top plate removed. 1 is a perspective view of a projector according to an embodiment of the present invention with a top plate removed. Explanatory drawing which shows the flow of the air of the projector which concerns on the Example of this invention. FIG. 3 is a diagram schematically illustrating image formation by a projection-side optical system in a projector according to an embodiment of the invention. FIG. 2 is a half sectional view showing an example of a projection-side optical system in a projector according to an embodiment of the invention. The figure which shows the other Example of the bonding lens fixation in the projection side optical system which concerns on the Example of this invention. The figure which shows the flow of the air of the optical system unit vicinity which concerns on the Example of this invention.

Explanation of symbols

10 Projector 11 Top plate
12 Front plate 13 Back plate
14 Right side plate 15 Left side plate
16 Bottom plate 17 Exhaust hole
18 Air intake hole 19 Lens cover
20 Louver 21 Input / output connector
22 I / O interface 23 Image converter
24 Display encoder 26 Display drive
31 Image compression / decompression unit 32 Memory card
35 Ir receiver 36 Ir processor
37 Key / Indicator section 38 Control section
41 Power supply control circuit 43 Cooling fan drive control circuit
45 Lens motor 47 Audio processor
48 Speaker
51 Display element 53 Display element heat sink
55 Cover glass 57 Condenser lens
63 Light source device 64 Discharge lamp
71 Color wheel 72 First reflection mirror
73 Wheel motor 74 Second reflection mirror
75 Light tunnel
77 Optics unit
78 Lighting block 79 Image generation block
80 Projection side block
83 Light source side lens group
84 Irradiation mirror
86 Optical system control board
90 Projection side optical system
91 Fixed lens tube 93 Fixed lens group
95 First movable lens tube 96 First movable lens group
97 Second movable lens barrel 98 Second movable lens group
101 Lamp power circuit block
102 Power supply control circuit board 103 Control circuit board
110 Blower 111 Air inlet
113 Discharge port 120 Partition wall
121 Inlet side space 122 Exhaust side space
123 1st partition 124 2nd partition
125 3rd partition 127 Lighting side block partition
128 Gap 129 Cutout
151 Thermal conduction tube 153 Radiation fin
155 Bonding lens
158 Stopper ring 159 Spacer ring
161 Holding cylinder
163 First sliding groove 165 Second sliding groove
167 1st cam pin 168 2nd cam pin
171 1st cam cylinder 173 1st cam groove
175 Second cam cylinder 177 Second cam groove

Claims (9)

  A projection-side optical system comprising: a lens barrel in which a plurality of lenses including a bonded lens are housed and fixed in a lens barrel, and a fixing portion of the bonded lens is a heat conducting lens barrel portion made of a good thermal conductor.   2. The projection-side optical system according to claim 1, wherein the heat conducting lens barrel is formed of a metal such as an aluminum alloy or a copper alloy which is a good heat conductor.   The projection-side optical system according to claim 1, wherein the heat conducting lens barrel portion has a heat radiating fin on an outer periphery thereof.   4. The projection-side optical according to claim 1, wherein a lens having a high coefficient of thermal expansion in the bonded lens is fixed with its outer periphery being in close contact with the heat conducting lens barrel. system. A light source device;
A light source side optical system;
A display element;
A projection-side optical system;
A cooling fan,
Lamp power circuit and projector control means,
The projection-side optical system includes a cemented lens in a lens group.   6. The lens barrel according to claim 5, wherein a plurality of lenses including a bonded lens are housed and fixed in a lens barrel, and the fixing portion of the bonded lens includes a lens barrel that is a heat conducting barrel portion by a good thermal conductor. projector.   7. The projector according to claim 5, wherein the heat conducting lens barrel is formed of a metal such as an aluminum alloy or a copper alloy which is a good heat conductor.   The projector according to any one of claims 5 to 7, wherein the heat-conducting lens barrel portion has a heat radiating fin on an outer periphery thereof.   The projector according to any one of claims 5 to 8, wherein a lens having a high thermal expansion coefficient in the bonded lens is fixed so that an outer periphery thereof is in close contact with the heat conducting lens barrel.

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