JP3061685U - Light source device for projector using multiple lamps - Google Patents

Abstract

(57) [Summary] [Object] A light source system that uses a plurality of small power lamps as a means for increasing the screen illuminance of a projector and increases the screen illuminance. A light beam from a plurality of light source devices that emits parallel light beams toward a special reflecting mirror provided in a projector is incident on the light source device, so that reflected light is converted into parallel light beams having the same optical axis.

Description

[Detailed description of the invention]

[0001]

[Industrial applications]

 The present invention is a means for increasing the screen illuminance in an optical projector using a light source. Use multiple low power lights instead of a single high power light. In a liquid crystal panel projector in which the emitted light is a parallel light beam and the transmitted light beam requires a parallel light beam, there is an advantage that it can be used as it is.

[0002]

[Prior art]

 Older means have increased the amount of light by increasing the power consumption of the light source lamps as a means to increase the screen illuminance of the projector. The use of high power lamps caused various problems. In the case of a tungsten halogen lamp, the light source area of a high-voltage lamp was large, and the light beam could not converge to the pupil position of the projection lens, which could be extended later, and the objective could not be achieved. Even with low-pressure tungsten halogen lamps, there was a problem with the current capacity of the filament, and the limit was approached.

In a discharge lamp, a large power lamp has a large volume, a high internal pressure, and requires an ultra-high voltage device for lighting. Accordingly, a lighting control device is also increased in size, and explosion proof of the lamp, insulation of electric power and the like are required. The problem derives. In recent years, the research and development of multiple uses of low-power lamps has been led from the two points of explosion-proof and thermal diffusion of lamps.

[0004]

[Problems to be solved]

 The condition for the light source of the projector is that the luminous flux distribution is rotationally symmetrical with respect to the optical axis of the projection lens.When using multiple lamps instead of a single lamp, the luminous flux passing through the material to be projected is projected with a simple arrangement. It is rotationally symmetric with respect to the lens axis, and the light flux distribution is not substantially uniform. Simply using an anti-reflection prism to unite the optical axes having different angles is possible, but the problem is to increase the screen illuminance, and each of them has a loss of 50% or more. The use of transparent prisms is out of the question.

[0005] Each lamp of the light source has an optical axis of each lamp, and has a light quantity distribution symmetrical to the optical axis of each lamp. When illuminating a material with a large number of lamps, the illuminance rises due to the luminous flux of the large number of lamps, but there is a difference in the angle of incidence of each lamp. And does not converge on the pupil position of the projection lens, and cannot pass through the projection lens, so that the illuminance of the projection screen cannot be increased. By making the optical axes of the individual lamps the same, the entire light beam converges on the pupil position of the projection lens, and the illuminance of the screen can be increased.

[0006]

[Technology to solve the problem]

 In order to solve the problem, the individual light sources were converted to parallel rays and the entire light beam was made uniform, so that the optical axis was replaced with the center of the light beam, and the occurrence of the edge of the Fresnel lens optical system, which was likely to occur, was avoided. . By converting the light beam into a parallel light beam, all the light beams can be treated in the same manner as the optical axis, and the difference in the exit angle due to the difference in the incident angle can be eliminated. That is, the incidence, reflection, and refraction established on the optical axis can be applied to all light beams.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 shows a conceptual diagram of an arrangement example of a lamp of a conventional projector and materials to be irradiated. Since a single lamp is used, the above condition can be satisfied by placing the lamp on the optical axis of the projection lens. Light source 11. The light beam emitted from the lens is condensed. 13. projection lens 12. While collecting light at the pupil position Through. Document 1
3. Is a projection lens. Is placed at the projection focus position. FIG. Shows an example of the layout of the data surface and the lamp in the present invention. 21. The reflecting mirror according to claim 1 on the bottom surface of the projector. 21. Place parallel light sources on the left and right of the document surface 23. Superimpose the luminous flux from
To be incident. The light beam transmitted through the material is a condenser lens 25. Projection lens 24. Is condensed at the pupil position and reaches the screen. FIG. Shows the optical contents of the lamp and the reflecting mirror in the present invention. The surface reflection prism having the apex angle of 120 ° reflects a light beam that forms an angle of 30 ° with the normal of a side forming a triangle at a reflection angle of 30 °. Thus, the light beam incident at 30 ° is emitted as a parallel light beam. At this time, the opposite surface of the reflecting prism has the same angle as the incident light beam, and does not block the light beam. The opposite is true from the symmetrical arrangement, and the combination of two light sources is established here. FIG. Shows an example of a multi-light irradiation system in the present invention.
FIG. By using the combined light source shown in (1) and superimposing, a light source having a large number of lamps can be obtained. The figure shows an example of three lamps.

[0008]

FIG. Is a light source device having a circular cross section using a combination of a light source lamp, a reflecting mirror, and a Fresnel lens. By obliquely cutting this light beam, the cross-section becomes inevitably elliptical, and even if the reflecting mirror and the data surface are rectangular, it can be easily handled. If the document surface is square, Fig.4. This can be achieved by rotating the composite light source at 90 °.

[0009]

As a means for making the axes of the light sources of a plurality of lamps the same, there has been a system utilizing total reflection of a prism. Although a transparent material having plasticity was required for the prism, the present invention is characterized in that it need not be a transparent material. Materials used in optics are required to have high requirements in order to obtain high-quality images, that is, transparency, uniformity, easy processing, weathering resistance, and the like. In the present invention, the material is used as a reflecting surface and does not transmit a light beam.

A light source device used in a projector is required to have a small amount of heat generation, but the amount of heat generation is substantially determined by power consumption and there is no great difference. In addition, large power lamps have a large lamp volume, high internal pressure, and a high risk of explosion. In a recently used discharge lamp system, a power supply device associated with the lamp has a large number of parts used depending on the power consumption of the lamp, and the power supply device as a whole becomes large. If the power consumption of the lamp is reduced, the parts related to electricity become smaller and dispersed, so that explosion-proof and insulation can be facilitated as compared with the use of a large lamp.

[Submission date] April 30, 1999

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Detailed explanation of the device

[Correction method] Change

[Correction contents] [Detailed description of the invention]

[0001]

[Industrial applications]

 The present invention is a means for increasing the screen illuminance in an optical projector using a light source. Use multiple low power lights instead of a single high power light. In a liquid crystal panel projector in which the emitted light is a parallel light beam and the transmitted light beam requires a parallel light beam, there is an advantage that it can be used as it is.

[0002]

[Prior art]

 Older means have increased the amount of light by increasing the power consumption of the light source lamps as a means to increase the screen illuminance of the projector. The use of high power lamps caused various problems. In the case of a tungsten halogen lamp, the light source area of a high-voltage lamp was large, and the light beam could not converge to the pupil position of the projection lens, which could be extended later, and the objective could not be achieved. Even with low-pressure tungsten halogen lamps, there was a problem with the current capacity of the filament, and the limit was approached.

In a discharge lamp, a large power lamp has a large volume, a high internal pressure, and requires an ultra-high voltage device for lighting. Accordingly, a lighting control device is also increased in size, and explosion proof of the lamp, insulation of electric power and the like are required. The problem derives. In recent years, the research and development of multiple uses of low-power lamps has been led from the two points of explosion-proof and thermal diffusion of lamps.

[0004]

[Problems to be solved] The condition of the light source of the projector is that the light flux distribution is rotationally symmetrical with respect to the optical axis of the projection lens. The light beam passing through the document is rotationally symmetric with respect to the axis of the projection lens, and the light beam distribution is not substantially uniform. Simply using an anti-reflection prism to unite the optical axes having different angles is possible, but the problem is to increase the screen illuminance, and each of them has a loss of 50% or more. The use of transparent prisms is out of the question.

[0005] Each lamp of the light source has an optical axis of each lamp, and has a light quantity distribution symmetrical to the optical axis of each lamp. When illuminating a material with a large number of lamps, the illuminance rises due to the luminous flux of the large number of lamps, but there is a difference in the angle of incidence of each lamp. And does not converge on the pupil position of the projection lens, and cannot pass through the projection lens, so that the illuminance of the projection screen cannot be increased. By making the optical axes of the individual lamps the same, the entire light beam converges on the pupil position of the projection lens, and the illuminance of the screen can be increased.

[0006]

[Technology to solve the problem]

 In order to solve the problem, the individual light sources were converted to parallel rays and the entire light beam was made uniform, so that the optical axis was replaced with the center of the light beam, and the occurrence of the edge of the Fresnel lens optical system, which was likely to occur, was avoided. . By converting the light beam into a parallel light beam, all the light beams can be treated in the same manner as the optical axis, and the difference in the exit angle due to the difference in the incident angle can be eliminated. That is, the incidence, reflection, and refraction established on the optical axis can be applied to all light beams.

FIG. FIG. 1 shows a conceptual diagram of an arrangement example of a lamp of a conventional projector and a material to be irradiated. Since a single lamp is used, the above condition can be satisfied by placing the lamp on the optical axis of the projection lens. Light source 11. The light beam emitted from the lens is condensed. 13. projection lens 12. While collecting light at the pupil position Through. Document 13. Is a projection lens. Is placed at the projection focus position. FIG. Shows an example of the layout of the data surface and the lamp in the present invention. 21. The reflecting mirror according to claim 1 on the bottom surface of the projector. 21. Parallel light beams on the left and right of the document surface 23. Superimpose the luminous flux from To be incident. The light beam transmitted through the document is a condenser lens 25. Projection lens 24. The light is focused at the pupil position and reaches the screen. FIG. Shows the optical contents of the lamp and the reflecting mirror in the present invention. A surface reflecting prism having a vertex angle of 120 ° reflects a light beam which forms an angle of 30 ° with a normal of a side forming a triangle at a reflection angle of 30 °. Thus, the light beam incident at 30 ° is emitted as a parallel light beam. At this time, the opposite surface of the reflecting prism has the same angle as the incident light beam, and does not block the light beam. The opposite is true from the symmetrical arrangement, and the synthesis of the two light sources is established here. FIG. Shows an example of a multi-light irradiation system in the present invention. FIG. By using the combined light source shown in (1) and superimposing, a light source with many lamps can be obtained. The figure shows an example of three lamps.

[0008]

【Example】

 FIG. The collimated light device used for the above was a light source device with a circular cross section using a combination of a light source lamp, a reflecting mirror, and a Fresnel lens. By obliquely cutting this light beam, the cross-section becomes necessarily elliptical, and even if the reflector and the data surface are rectangular, it can be easily handled. If the document surface is square, Fig.4. This can be done by rotating the composite light source that can be placed at 90 °.

[0009]

[Effect of the invention]

 As a means for making the axes of the light sources of a plurality of lamps the same, there has been a method using total reflection of a prism. Although a transparent material having plasticity was required for the prism, the present invention is characterized in that it does not need to be a transparent material. Materials used in optics are required to have a high degree of quality in order to obtain high-quality images. That is, transparency, uniformity, easy processing, weathering resistance, and the like are mentioned. In the present invention, the material is used as a reflecting surface and does not transmit a light beam.

[0010] A light source device used in a projector is required to generate a small amount of heat, but the amount of heat generated is substantially determined by power consumption and does not greatly differ. In addition, large power lamps have a large lamp volume and high internal pressure, which increases the danger of explosion and increases explosion prevention measures. In the recently used discharge lamp system, the power supply device attached to the lamp has a large number of parts used due to the power consumption of the lamp and the entire power supply device becomes large. If the power consumption of the lamp is reduced, the parts related to electricity are made smaller and distributed, so that explosion proof and insulation can be made easier compared to using a large lamp.

[Brief description of the drawings]

FIG. 1 shows a conceptual diagram of an example of a layout of a lamp and a material to be irradiated of a conventional projector.

FIG. 2 shows an example of an arrangement of a data surface and a lamp in the present invention.

FIG. 3 shows the optical contents of the lamp and the reflecting mirror in the present invention.

FIG. 4 shows an example of a multiple-light irradiation system in the present invention.

Claims (2)

[Utility model registration claims] 1. A bottom surface of a triangular prism having a cross section with a vertex angle of 120 ° ± 3 ° as a light source of a projector and having a vertex angle of 120 ° ± 3 ° is arranged in parallel with a number of YZ planes having an optical axis as an X axis. When the ridgeline of the apex angle is parallel to the Y axis, a light source that emits parallel rays is installed symmetrically to the X axis in the XZ plane, and the axis of the light source is set to an incident angle of 30 ° ± 3 ° with the Z axis. When the luminous flux is 3
A light source device that is reflected by the group of angular prisms, travels parallel to the X axis, and becomes a coaxial parallel light beam. 2. A multiple lamp light source device using the combination of claim 1 by imitating the light source device of claim 1 as a single parallel light source.