JP2007179966A - Lamp unit and projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lamp unit and the like which suppresses leakage of light from an end of a sealing part while enhancing the heat radiation characteristic of the sealing part. <P>SOLUTION: The lamp unit includes a lamp 23 and a reflecting mirror 24 which reflects light emitted from the lamp 23 in a predetermined direction. The lamp 23 includes a light emission part and sealing parts 45 provided on both sides of the light emission part. The sealing part 45 is held to the reflecting mirror 24 through a cement 87. The end of the sealing part 45 is covered with a metal cap 77. The metal cap 77 is equipped with a lid part and a cylindrical part. The end of the opening side of the cylindrical part is covered with the cement 87, and the inner surface of the lid part contacts directly with the end surface of the sealing part 45. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a lamp unit including a high-pressure discharge lamp and a reflecting mirror, and a projector having the lamp unit.

  As a lamp unit for a projector, for example, a high-pressure discharge lamp (hereinafter simply referred to as “lamp”) having a light emitting portion and a pair of sealing portions provided on both sides of the light emitting portion, and a concave reflecting surface And a reflecting mirror having a cylindrical holding portion formed on the bottom side of the reflecting surface, and with a sticking agent such as cement in a state where one sealing portion of the lamp is inserted into the holding portion of the reflecting mirror Some are fixed. At that time, the end portion of the sealing portion was not entirely covered with the adhesive, but was exposed from the adhesive.

In contrast, in particular, in recent years, the entire end of the sealing portion is covered with cement so that light does not leak outward from the end of the sealing portion held by the holding portion (for example, a patent Document 1) and those in which a base covering the end part is bonded to the end part of the sealing part with cement (for example, Patent Document 2).
In addition, due to light leakage from the end of the sealing portion, a member disposed behind the lamp unit is deteriorated by ultraviolet rays contained in the light, or an ambient temperature around the lamp is increased by heat rays, so that the cooling effect is weakened. Or
JP 2005-259678 A FIG. 3 of JP2003-68184A

However, the lamp unit with the light leakage countermeasure has the following problems. That is, in both measures, the end of one sealing part is buried in the cement. Cement usually has a low thermal conductivity, so the heat generated from the electrode when the lamp is lit is transferred into the cement, and as a result, the sealing portion becomes hot and cracks are likely to occur.
The present invention has been made in view of the above-described problems, and provides a lamp unit and a projector that can improve heat dissipation characteristics of a sealing portion while suppressing light leakage from an end portion of the sealing portion. The purpose is to provide.

  In order to achieve the above object, a lamp unit according to the present invention includes a high pressure discharge lamp having a sealing portion extending from a light emitting portion having a discharge space, and a concave reflecting surface in which the high pressure discharge lamp is incorporated. The reflecting mirror has a cylindrical holding portion in which the sealing portion is inserted and the sealing portion is held via an adhesive, and the reflecting mirror The sealing portion held by the metal member is covered with a metal member whose end portion is in direct contact with the end portion, and a portion not covered with the metal member is covered with an adhesive, The surface opposite to the sealing portion is exposed to the outside air.

  The term “direct contact” as used herein refers to a state in which the surface of the sealing portion and the surface of the metal member are in contact with each other and heat can be conducted between the sealing portion and the metal member. Therefore, no sticking agent such as cement is interposed between the sealing portion and the metal member. However, in particular, since the sealing portion is formed into a predetermined shape and size by glass processing, it may be difficult to obtain high dimensional accuracy, and as a result, a gap is formed between the sealing portion and the metal member. There is a case. Then, when the sealing portion is held in the holding portion of the reflecting mirror via the sticking agent, the sticking agent may inevitably enter the gap, but even in that case, the “direct contact” referred to here It corresponds to.

  The “high pressure discharge lamp” is a concept including a high pressure mercury lamp, a metal halide lamp, and the like. Further, the lamp unit may hold the sealing portion of the high-pressure discharge lamp with a reflecting mirror, and the number of sealing portions may be one or more. That is, it is sufficient that at least one sealing portion of the high-pressure discharge lamp is held by the reflecting mirror, and it may or may not have a sealing portion other than the sealing portion.

On the other hand, the metal member has a cap shape covering an end of the sealing portion, and is connected to an electrode disposed in the discharge space from the end surface of the sealing portion. A lead wire to be led out, and the metal member has a through-hole through which the lead wire is inserted.
Further, the high-pressure discharge lamp has a trigger wire for lowering a starting voltage, and the metal member is attached to the lead wire at a position opposite to the sealing portion in the metal member. And it is equipped with the said sealing part, It is characterized by the above-mentioned.

  In order to achieve the above object, a projector according to the present invention includes a lamp unit having a high-pressure discharge lamp and a reflecting mirror, and the lamp unit is a lamp unit having the above-described configuration.

  In the lamp unit according to the present invention, since the sealing portion held by the reflecting mirror (holding portion) is covered with the metal member and the fixing agent, the light emitted from the sealing portion is outside the lamp unit. Can be prevented from leaking. Moreover, since the metal member is in direct contact with the sealing portion and exposed to the outside air, the heat generated during lighting can be transferred to the sealing portion and the metal member, and then released to the outside air. In particular, the heat dissipation characteristics of the sealing portion can be enhanced.

  On the other hand, since the projector according to the present invention includes the lamp unit, the same effect can be obtained.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
1. Projector FIG. 1 is a perspective view in which a part of a projector according to an embodiment is cut away.
The projector 1 is a so-called front projection type, and as shown in FIG. 1, a lamp unit 3 including a high-pressure discharge lamp (hereinafter simply referred to as “lamp”), and an electronic stability for lighting the lamp. The case 13 includes a power supply unit 5 including a controller, a control unit 7, a lens unit 9 including a condensing lens, a transmissive color liquid crystal display panel, and a drive motor, a cooling fan device 11, and the like. The lens unit 9 is provided so that a part of the lens unit 9 protrudes outside the case 13.

The power supply unit 5 converts a household AC100V power supply into a predetermined DC voltage and supplies it to an electronic ballast, a control unit 7 or the like. The power supply unit 5 includes a substrate 15 disposed on the upper portion of the lens unit 9 and a plurality of electronic / electrical components 17 mounted on the substrate 15.
The control unit 7 displays a color image by driving a color liquid crystal display panel based on an image signal input from the outside. Further, a focusing motor and a zooming operation are executed by controlling a driving motor arranged in the lens unit 9.

The light emitted from the lamp unit 3 is condensed by a condenser lens disposed inside the lens unit 9 and is transmitted through a color liquid crystal display panel disposed in the middle of the optical path. As a result, the image formed on the color liquid crystal display panel is projected onto a screen (not shown) via the lens 19 or the like.
2. Lamp Unit (1) Configuration of Lamp Unit FIG. 2 is a diagram showing the configuration of the lamp unit according to the embodiment, and a part of the reflecting mirror is cut away so that the state of the lamp in the reflecting mirror can be understood. . In FIG. 1, description of electrical wiring and the like related to the lamp unit is omitted.

  As shown in FIG. 2, the lamp unit 3 includes a lamp 23 and a reflecting mirror 24 that reflects light emitted from the lamp 23 in a predetermined direction, and external lead wires 61 and 63 led out from both ends of the lamp 23. Are connected to the power supply unit 5 (not shown) through a pair of lead wires 25 and 27 connected to the connector and connectors 29 and 31 connected to the other ends of the lead wires 25 and 27.

(2) Configuration of Lamp FIG. 3 is a diagram showing a configuration of the lamp according to the embodiment of the present invention.
As shown in FIG. 3, the lamp 23 includes a discharge vessel 48 including a light emitting portion 43 having a discharge space 41 therein and sealing portions 45 and 47 provided on both sides of the light emitting portion 43, and the discharge Electrode structures 49 and 51 sealed to both sealing portions 45 and 47 in a state where tip portions (which will be described later) are substantially opposed to each other inside the space 41 are provided. The discharge space 41 is filled with a predetermined amount of mercury, a rare gas for starting assistance, and a halogen substance for halogen cycle as a luminescent substance.

The electrode structures 49 and 51 are formed by connecting electrodes 53 and 55, metal foils 57 and 59, and external lead wires 61 and 63 in this order (for example, fixed by welding).
The external lead wires 61 and 63 are led out of the discharge vessel 48 from the end surfaces of the sealing portions 45 and 47 opposite to the light emitting portion 43. As shown in FIG. 2, the external lead wire 63 is led out to the outside of the reflecting mirror 24 through the through hole 65 formed in the reflecting mirror 24 and connected to the lead wire 27.

The electrodes 53 and 55 are disposed inside the discharge space 41 so as to face each other on a substantially straight line. The lamp 23 is of a so-called “short arc” type, and is close to a point light source. Therefore, the distance between them, that is, the distance between the electrodes is set in a range of 0.5 mm to 2.0 mm, for example.
The electrodes 53 and 55 include electrode shafts 67 and 69 and electrode coils 71 and 73 provided at the tips of the electrode shafts 67 and 69. In addition, the electrode may be comprised with the material from which an electrode axis | shaft and an electrode coil differ, and may be comprised with the same material.

  In the manufacturing process, the electrode structures 49 and 51 are inserted into the glass tube constituting the discharge vessel 48, and then the glass is formed in a state where the distance between the electrodes 53 and 55 is set to a predetermined size in the space to be the discharge space 41. Among the tubes, the predetermined portions of the sealing portions 45 and 47 are sealed by a known shrink sealing method, and the portions where the metal foils 57 and 59 are mainly sealed are sealed. Thereby, a discharge space 41 is formed inside the light emitting unit 43. In a state where the electrode structures 49 and 51 are sealed, the electrodes 53 and 55 extend from the sealing portions 45 and 47 to the discharge space 41 as shown in FIG.

One of the sealing portions 45 and 47, here, the sealing portion 45 is held by a holding portion 85 of the reflecting mirror 24 described later.
A trigger wire 75 for lowering the starting voltage when the lamp is lit is wound around the outer periphery of the sealing portion 47 on the light emitting portion 43 side. The trigger wire 75 is wound around the outer periphery of the sealing portion 47 a plurality of times, here, about four times, and the other sealing portion 45 is disposed along the outer surface across the light emitting portion 43. It is connected to an external lead 61 that is led out from the end face.

4 is an enlarged view of an end portion of the sealing portion of the lamp as viewed from the direction A in FIG. 3, and FIG. 5 is an enlarged view of the periphery of the end portion of the sealing portion of the lamp in FIG.
The end portion of the sealing portion 45 is an end surface 45a of the sealing portion 45 and a metal cap that is the outer periphery of the sealing portion 45 and covers the vicinity of the end surface 45a (the “metal member” of the present invention). ) 77 is installed. As shown in FIG. 5, the metal cap 77 has a shape along the shape of the end portion of the sealing portion 45. That is, the metal cap 77 is slightly larger than the diameter of the sealing portion 45, and as shown in FIG. 4, a lid portion 77 b having a through hole 77 a at a position corresponding to the external lead wire 61, and a cross section of the sealing portion 45. And a cylindrical portion 77c having a cross-sectional shape similar to the shape of. Since the metal cap 77 has the lid portion 77b that is slightly larger than the diameter of the sealing portion 45, there is a gap between the outer peripheral surface of the sealing portion 45 and the cylindrical portion 77c. However, this is because the sealing portion 45 is made of glass, and it is difficult to obtain high dimensional accuracy, and therefore has a tolerance. On the other hand, in the step of attaching the metal cap 77 to the end portion of the sealing portion 45, it is possible to equidistant between the outer peripheral surface of the end portion of the sealing portion 45 and the inner surface of the metal cap 77 over the entire circumference. It is difficult, and the metal cap 77 is substantially attached to the sealing portion 45 in a biased manner, and the outer peripheral surface of the sealing portion 45 and the inner peripheral surface of the metal cap 77 are in surface contact with each other at a part thereof.

  As shown in FIG. 3, in the metal cap 77, the external lead wire 61 led out from the end face 45a of the sealing portion 45 is drawn out through the through hole 77a of the lid portion 77b, and the lid portion 77b is sealed. In the state where the end portion of the sealing portion 45 is covered so as to be in direct contact with the end surface 45a, the end portion on the sealing portion 45 side of the trigger wire 75 is wound around the external lead wire 61, and the winding portion 75a is By being formed, it is attached to the sealing portion 45. As shown in FIG. 4, the through hole 77 a of the lid portion 77 b is larger than the diameter of the external lead wire 61 and smaller than the outer diameter of the winding portion 75 a around which the trigger wire 75 is wound around the external lead wire 61.

(3) Reflector Mirror Next, the reflector 24 will be described.
As shown in FIG. 2, the reflecting mirror 24 includes a reflecting portion 83 having a concave reflecting surface 81 on the inner surface, and a bottom portion of the reflecting portion 83 on the side opposite to the reflecting surface 81 (indentation direction of the reflecting surface 81). And a cylindrical holding portion 85 that holds the sealing portion 45 of the lamp 23 therein. That is, the shape of the reflecting mirror 24 is funnel-shaped, and the holding portion 85 that protrudes outward is provided at a portion having a small opening diameter. The reflecting mirror 24 is, for example, a dichroic reflecting mirror.

FIG. 6 is an enlarged view seen from the direction C of FIG. 2 is an irregular cross-sectional view of the line BB in FIG. 6 as viewed from the direction of the arrow.
As shown in FIG. 2, the lamp 23 is assembled into the reflecting mirror 24 by inserting the sealing portion 45 into the holding portion 85 by a predetermined size, and the focal point of the reflecting mirror 24 and the pair of electrodes 53, In a state where the lamp 23 is aligned so that the central position of the interval 55 is substantially coincident with each other, they are fixed to each other through a fixing agent, here, cement 87 in the gap between the sealing portion 45 and the holding portion 85. Is done.

  When the cement 87 is injected into the gap, as shown in FIGS. 2 and 4, the opening periphery of the metal cap 77, that is, the edge opposite to the lid portion 77 b in the cylindrical portion 77 c is not exposed, and The outer surface of the metal cap 77 (specifically, the outer peripheral surface of the cylinder portion 77c) is covered with the cement 87 so that a part of the metal cap 77, for example, the lid portion 77b comes into contact with the atmosphere. Thereby, in a state where the lamp 23 is incorporated in the reflecting mirror 24, the sealing portion 45 of the lamp 23 is surely free from the portion exposed to the atmosphere.

3. Other Configurations As shown in FIG. 2, the lead wires 25, 27 include coated conductors 99, 101 that cover conductive core materials 95, 97 with insulating coating materials 96, 98, and the coated conductors 99, 101 includes nickel wires 103 and 105 connected to core members 95 and 97 on the side connected to the external lead wires 61 and 63 of the lamp 23.

The core members 95 and 97 and the nickel wires 103 and 105 are connected by connecting the inner core members 95 and 97 and the nickel wires 103 and 105 exposed by peeling off the cover members 96 and 98 of the coated conductors 99 and 101 to the connecting sleeve 107, This is performed by caulking the connection sleeves 107 and 109 so as to overlap inside 109.
The connection between the lead wires 25 and 27 and the external lead wires 61 and 63 of the lamp 23 is performed by caulking the connection sleeves 107 and 109 in which the tips of the nickel wires 103 and 105 are inserted, and the connection sleeves 107 and 109 are connected to the outside. The lead wires 61 and 63 are welded.

On the other hand, as shown in FIG. 2, the lead wires 25 (27) and the connectors 29 (31) are connected to the cores 95 (97) inside the covering material 96 (98) by the connectors 29 (31). ) Is fixed by fixing the covering materials 96, 98 to the fixing portion 117 of the connector 29 (, 31) so as to extend into the connection portion 115.
4). Lamp lighting A case where the lamp unit 3 having the above-described structure is turned on will be described.

First, the lamp 23 is turned on with the approximate center between the pair of electrodes 53 and 55 inside the light emitting unit 43 as the light emission center.
The light emitted from the light emission center toward the reflection surface 81 travels as it is and is emitted to the outside of the lamp 23. This light is reflected in a predetermined direction by the reflecting surface 81 and is emitted forward from the lamp unit 3. On the other hand, the light emitted from the light emission center toward the inside of the sealing portion 45 held by the holding portion 85 of the reflecting mirror 24 propagates through the inside of the sealing portion 45 while the end portion (end surface) of the sealing portion 45. 45a).

  And the light which reached the edge part of the sealing part 45 is radiate | emitted from the sealing part 45 outside. At this time, the end portion of the sealing portion 45 is covered with the metal cap 77, and the edge of the metal cap 77 on the light emitting portion 43 side is covered with the cement 87. Is reflected by the inner surface of the metal cap 77 and the cement 87. For this reason, almost no light is emitted from the end of the sealing portion 45 of the lamp 23 to the outside of the lamp 23 (leaks from the end).

  Further, since the metal cap 77 is in direct contact with the surface of the sealing portion 45 and the lid portion 77b is exposed to the outside air on the surface opposite to the sealing portion 45, the heat at the time of lighting the lamp is the light emitting portion. 43, is transferred to the sealing portion 45 and the metal cap 77, and is discharged from the lid portion 77b of the metal cap 77 to the outside air. Thereby, the temperature rise of the sealing part 45 at the time of lamp lighting can be suppressed (the temperature rise will be described in the column of temperature measurement at the time of lighting described later).

  In addition, if the temperature rise of the sealing part 45 can be suppressed, the full length of the sealing part 45 can be shortened, for example. In other words, leakage occurs between the sealing member and the electrode structure because the temperature of the sealing part rises when the lamp is lit, and cracks due to differences in thermal expansion between the sealing part and the electrode structure occur. It is thought to be the cause. For this reason, the length of the sealing portion is designed so that the temperature of the sealing portion is lower than the temperature at which leakage may occur. Since the temperature of the sealing portion decreases as the position becomes farther from the light emitting portion, the better the heat dissipation characteristics of the sealing portion, the shorter the length of the sealing portion.

5. Temperature measurement during lighting (1) About the lamp unit for measurement The lamp unit according to the present embodiment in which the end of the sealing portion held by the reflecting mirror in the lamp is covered with a metal cap 77 (hereinafter referred to as “invention product”). Lamp unit ”) and a conventional lamp unit (hereinafter referred to as a“ conventional lamp unit ”) in which the entire end of the sealing portion held by the reflector in the lamp is covered with cement. The surface temperature of the sealing part on the side held by the reflecting mirror was measured.

FIG. 7 is a diagram for explaining the measurement of the surface temperature at the sealing portion of the lamp.
First, as shown in FIG. 7A, one sealing part 137 of the lamp 135 is inserted into the holding part 133 of the reflecting mirror 131, and the cement 139 is inserted between the holding part 133 and the sealing part 137. The lamp 135 and the reflecting mirror 131 are fixed by the cement 139. Then, the temperature sensor 141 is attached to a portion where the cement 139 is not applied in the sealing portion 137 fixed with the cement 139.

  Next, in the lamp unit 143 for the inventive product, as shown in FIG. 7B, the end portion of the sealing portion 137 of the lamp 135 is covered with a metal cap 145. Then, the coated metal cap 14 is fixed with cement. Specifically, the cement 147 is applied to the cylindrical portion of the metal cap 145 and the outer peripheral surface of the sealing portion 137 to which the cement 139 is not applied (in FIG. 7B, the cement 147 Including code “147”). Thus, the inventive lamp unit 143 is completed.

  On the other hand, in the conventional lamp unit 149, as shown in FIG. 7C, the cement 151 is further applied to the portion of the sealing portion 137 of the lamp 135 where the cement 139 is not applied ( In FIG.7 (c), the cement 151 is set to the code | symbol "151" including the cement 139.) The edge part of the sealing part 137 of the lamp | ramp 135 is completely coat | covered. Thereby, the conventional lamp unit 149 is completed.

Note that the lamp 135 used for the measurement has a rated lamp power value of 165 W, and the reflecting mirror 131 is a square type whose opening has a square shape and whose one side is 50 (mm).
(2) Measurement result The lamp 135 of the above-mentioned two types of lamp units 143 and 149 was turned on, and when 20 minutes passed from the start of lighting, the surface temperature of the sealing portion 137 was measured using the temperature sensor 141. .

As a result of measuring the temperature as described above, in the inventive lamp unit 143 shown in FIG. 7B, the surface temperature of the sealing portion 137 of the lamp 135 was 206 (° C.). In contrast, in the conventional lamp unit 149 shown in FIG. 7C, the surface temperature of the sealing portion 137 of the lamp 135 was 225 (° C.).
From this result, it can be seen that the inventive lamp unit 143 has a temperature of the sealing portion 137 of about 20 (° C.) lower than the conventional lamp unit 149. This is considered to be because heat generated during lighting is released through the sealing portion 137 and the metal cap 145 by covering the end portion of the sealing portion 137 with the metal cap 145 in contact with the outside air.

As described above, the lower the temperature of the sealing portion, the more difficult it is to leak at the sealing portion, and the length of the sealing portion can be shortened. Therefore, according to the present invention, it is possible to prevent light from leaking from the sealing portion and to reduce the size of the lamp and the lamp unit.
6). Productivity The lamp unit 3 configured as described above includes a metal cap 77 that covers the end of the sealing portion 45 held by the reflecting mirror 24 in the lamp 23. The metal cap 77 is inserted with the external lead wire 61 led out from the end face 45a of the sealing portion 45 into the through hole 77a of the lid portion 77b, and the metal cap 77 and the sealing portion 45 are in contact with each other. The end portion of the trigger wire 75 on the sealing portion 45 side is wound around the external lead wire 61 outside the metal cap 77 (forms a winding portion 75a), thereby being attached to the lamp 23.

In other words, if the lamp 23 having the trigger wire 75 is used as the lamp of the lamp unit 3, it can be performed only by increasing the number of steps for covering the metal cap 77 on the predetermined sealing portion 45, and for mounting the metal cap 77. There is no significant increase in effort.
In addition, in the conventional method of covering the entire end of the sealing portion with cement, it is necessary to apply cement to the entire end, and when the end is covered with cement, heat is emitted when the lamp is turned on. Difficult to stay in cement. For this reason, in order to improve heat dissipation, it is necessary to manage the thickness of the cement corresponding to the end of the sealing portion, and it takes time to apply the cement.

However, in the present embodiment, it is only necessary to cover the opening edge of the metal cap 77 with the cement 87 so that the edge is not visible from the outside. There is no significant decline.
<Modification>
As mentioned above, although this invention has been demonstrated based on embodiment, it cannot be overemphasized that this invention is not restricted to an above-described form, For example, it can also be set as the following forms.

1. Metal member (1) Dimensions of metal cap In the embodiment, the dimension of the metal cap is not particularly described, but the lamp and the reflecting mirror among the sealing parts of the lamp held by the holding part of the reflecting mirror. What is necessary is just to be able to cover the portion where the cement is not applied (the sealing portion is exposed) when the amount of cement necessary for fixing is applied.

At this time, it is preferable to cover the exposed part of the sealing part from the holding part over the entire range, but a part of the exposed part (for example, half of the exposed part) is covered with cement and the remaining part is made of metal. You may make it coat | cover with a cap.
Further, the dimensions of the metal cap and the like are appropriately determined according to the specifications of the lamp unit. Furthermore, although the metal cap is a unit in which the lid and the cylinder are integrated, for example, the metal cap may be configured by combining separate lids and cylinders.

(2) About shape Although the metal member (a metal cap) in the embodiment has a cap shape, that is, a cylindrical shape having an end wall (lid portion), the metal member according to the invention has a cap shape. Other shapes may be used. Other shapes include, for example, a disk shape.
FIG. 8 is a diagram illustrating a modification of the shape of the metal member.

  A metal plate 202 covering the end surface of the sealing portion 45 is attached to the sealing portion 45 on the side of the lamp 200 held by the reflecting mirror 24. As is apparent from FIG. 8, the inner surface 202 a that is one main surface of the metal disk 202 is in direct contact with the end surface 45 a of the sealing portion 45. Further, the peripheral edge of the outer surface 202b which is the other main surface is covered with cement 204, and the central portion of the outer surface 202b is exposed to the outside air.

Further, as in the embodiment, the external lead wire 61 is led out from the end face 45a of the sealing portion 45, and a through hole 202c for allowing the external lead wire 61 to be inserted through substantially the center of the metal board 202. Is formed.
As in the embodiment, the metal plate 202 is fixed to the sealing portion 45 by causing the external lead wire 61 to be led out of the metal plate 202 from the through-hole 202c of the metal plate 202, so that the metal plate 202 is sealed. The trigger wire 206 is wound around the external lead wire 61 outside the metal board 202 in a state where the end wire 45 is in contact with the end surface 45a. In addition, the winding part wound around is 206b in the figure, and this winding part 206b blocks the through hole 202c of the metal board 202, and prevents light from leaking from the through hole 202c.

Even in such a configuration, leakage of light from the sealing portion 45 of the lamp 200 to the rear of the lamp unit 208 can be prevented, and the end portion (end surface 45a) of the sealing portion 45 and the metal plate 202 are in direct contact with each other. Therefore, the heat at the time of lamp lighting is transmitted from the sealing portion 45 to the metal plate 202, and is released from the metal plate 202 to the atmosphere.
(3) Size In the above embodiment and the above modification, the metal member covers the entire surface of the sealing portion except for the lead-out portion of the external lead wire, but the metal member is the end surface of the sealing portion. It is also possible to cover a part of this. However, in the case where a part is covered, the area covered with cement or the like is increased and the temperature of the sealing portion is higher than in the case where the entire surface is covered.

  Further, in the embodiment and the modification, the end surface of the sealing portion held by the reflecting mirror is covered with the metal member. However, for example, the metal member is made of cement without covering the end surface of the sealing portion. You may coat | cover only the said outer peripheral surface in the state which coat | covers an end surface and is in direct contact with the edge part outer peripheral surface except the end surface of a sealing part. However, when only the outer peripheral surface is covered with the metal member, the temperature of the sealing portion becomes higher than in the case where both the end surface and the outer peripheral surface are substantially entirely covered as in the embodiment.

(4) Fixing method In the embodiment and the modification, the trigger wire is used to fix the metal member, but the metal member may be fixed by other methods. As another method, for example, in a state where the sealing portion is in contact with the metal member, the external lead wire on the side opposite to the sealing portion of the metal member (that is, the outside of the metal member) is separated from the trigger wire. A metal wire may be wound.

Furthermore, the shape of the metal member may be the cap shape of the embodiment, and a trigger wire or a metal wire different from the trigger wire may be wound around the outer periphery of the tube portion, or the tube portion may be crimped to the sealing portion. It may be crimped. Moreover, you may make it fix only with the cement which coat | covers the opening periphery of a cylinder part.
Further, the metal member may be fixed to the lead wire by welding, and further, on the outer surface side of the metal member of the external lead wire inserted through the metal member with the metal member in direct contact with the sealing portion. The metal member can also be fixed by bending it immediately after the production.

2. Projection Type Projector Although a front projection type projector has been described as a projector in the embodiment, it may be other than a front projection type, for example, a rear projection type projector.
FIG. 9 is an overall perspective view of the rear projection type image display apparatus.
The rear projection type projector 250 includes a screen 254 for displaying an image or the like on the front wall of the cabinet 252, and the lamp unit 3 described in the above embodiment is provided inside the cabinet 252.

3. Lamp In the lamp described in the embodiment, a pair of electrodes extends from the sealing portion toward the discharge space on substantially the same line segment, and tip portions (electrode coils) thereof face each other on the line segment. However, the pair of electrodes may not be opposed to each other on the line segment (the same as the axis of the electrode shaft).

FIG. 10 is a view showing a lamp in which the extending direction of the electrodes is different from that of the embodiment.
As shown in FIG. 10, the lamp unit 300 includes a lamp 302 and a reflecting mirror 304, and the lamp 302 is held by a holding portion 306 of the reflecting mirror 304 via a cement 308 as in the embodiment.
As shown in FIG. 10, the lamp 302 includes a discharge vessel 316 including a light emitting unit 312 having a discharge space 310, a sealing unit 314 extending from the light emitting unit 312, and an inside of the discharge space 310. It consists of a pair of electrode structural bodies 316 and 318 that are sealed to the sealing portion 314 in a state in which the tip portions face each other. Note that mercury, a rare gas, a halogen gas, or the like is sealed in the discharge space 310 as in the embodiment.

Similarly to the embodiment, the electrode structures 316 and 318 are formed by connecting the electrodes 320 and 322, the metal foil, and the external lead wires 324 and 326 in this order, and the sealing portion 314 is mainly at the portion where the metal foil is present. Sealed. The external lead wires 324 and 326 are led out from the end face of the sealing portion 314.
The electrodes 320 and 322 include electrode shafts 328 and 330 whose tips are bent toward the other electrode side, and electrode coils 332 and 334 provided at bent portions of the electrode shafts 328 and 330, respectively.

  Here, unlike the electrodes in the embodiment, the electrode shafts 328 and 330 extend from the sealing portion 314 in parallel with each other, and the electrode coils 332 and 334 of the electrodes 320 and 322 face each other in the discharge space 310. Yes. The tip ends of the electrode shafts 328 and 330 are bent at about 90 degrees so that the electrodes 320 and 322 provided at the ends face each other on substantially the same line. In this case as well, the distance between the tips of the electrodes 320 and 322, that is, the distance between the electrodes is set in the range of 0.5 mm to 2.0 mm in the case of the short arc type.

The end of the sealing portion 314 opposite to the light emitting portion 312 is covered with a metal cap 336 as in the embodiment. Similar to the embodiment, the metal cap 336 has a lid portion and a cylindrical portion, and is attached to the sealing portion 314 in a state where the inner surface of the lid portion is in direct contact with the end surface of the sealing portion 314. .
The lamp 302 described here is provided with a pair of electrode components 316 and 318 in the sealing portion 314, so that the metal cap 336, the external lead wires 324 and 326 of the pair of electrode components 316 and 318, Alternatively, an insulation measure is required for the external lead wires 324 and 326 of at least one of the pair of electrode structures 316 and 318.

As shown in FIG. 10, the metal cap 336 is fixed to the reflecting mirror 304 by covering the end of the cylindrical portion with cement 308.
Each of the above-described modifications can be similarly applied to the lamp unit 300 described here.

  INDUSTRIAL APPLICABILITY The present invention can be used for a lamp unit or a projector that can suppress backward light leakage and a rise in the temperature of the sealing portion.

It is the perspective view which notched some projectors concerning an embodiment. It is a figure which shows the structure of the lamp unit which concerns on embodiment, and a part of reflectors etc. are notched so that the mode of the lamp | ramp etc. in a reflector may be understood. It is a figure which shows the structure of the lamp | ramp which concerns on embodiment of this invention. It is the enlarged view which looked at the edge part periphery of the sealing part of a lamp | ramp from the A direction of FIG. It is an enlarged view of the edge part periphery of the sealing part of the lamp | ramp of FIG. It is the enlarged view seen from the C direction of FIG. It is a figure explaining measurement of the surface temperature in the sealing part of a lamp. It is a figure which shows the modification about the shape of a metal member. It is a whole perspective view of a rear projection type image display device. It is a figure which shows the lamp from which the extension direction of an electrode differs from embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Projector 3 Lamp unit 23 Lamp 24 Reflector 43 Light emission part 45, 47 Sealing part 49, 51 Electrode structure 61, 63 External lead wire 75 Trigger wire 75a Winding part 77 Metal cap 77a Through-hole 77b Cover part 77c Tube part 87 cement

Claims (5)

A high-pressure discharge lamp in which a sealing portion extends from a light-emitting portion having a discharge space; and a reflecting mirror in which the high-pressure discharge lamp is incorporated and a concave reflecting surface is formed. A lamp unit having a cylindrical holding part in which a sealing part is inserted and holding the sealing part via an adhesive,
The sealing portion held by the reflecting mirror is covered with a metal member whose end is in direct contact with the end, and a portion not covered with the metal member is covered with an adhesive, and the metal A lamp unit, wherein a surface of the member opposite to the sealing portion is exposed to outside air. The lamp unit according to claim 1, wherein the metal member has a cap shape that covers an end portion of the sealing portion. A lead wire connected to an electrode disposed in the discharge space is led out from an end face of the sealing portion, and the metal member has a through-hole through which the lead wire is inserted. Item 3. The lamp unit according to Item 1 or 2. The high-pressure discharge lamp has a trigger wire for lowering the starting voltage, and the metal member is attached to the lead wire at a position opposite to the sealing portion in the metal member, The lamp unit according to claim 1, wherein the lamp unit is attached to the sealing portion. A projector comprising a lamp unit having a high-pressure discharge lamp and a reflecting mirror,
The projector according to claim 1, wherein the lamp unit is the lamp unit according to claim 1.

Images