JP2008083110A - Projector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a projector capable of forming two images by using one scanning mirror driving apparatus. <P>SOLUTION: Two light beams divided by a half mirror HM are made incident on the front face and the back face of a scanning mirror SM, respectively, and reflected on the respective faces. Thus, the scanning mirror SM provided with mirror faces on the front and the back sides, respectively, is driven by one scanning mirror driving apparatus, and the same images are simultaneously displayed on two screens SR1 and SR2. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projector capable of projecting an image on a screen.

Conventionally, a projector capable of projecting an image on a screen has been used. As a projector, there is a projector that projects an image on a screen by making light incident on a scanning mirror and scanning the light reflected by the scanning mirror on the screen. According to this projector, image generation is realized by the high-speed operation of the scanning mirror.
JP 2005-173097 A JP 2005-309162 A

  According to the projector using the scanning mirror, since only a mirror provided on one main surface of the flat scanning mirror is used, only one image can be formed by one scanning mirror. Further, since the swing width of the scanning mirror is limited, the image cannot be enlarged any more. If a plurality of scanning mirrors are used to solve the above-described problem, the structure of the scanning mirror driving device becomes complicated and the projector becomes large.

  The present invention has been made in view of the above problems, and one object thereof is to form two images using one scanning mirror driving device.

  Another object of the present invention is to form a large image using one scanning mirror driving device without increasing the swing width of the scanning mirror driving device, that is, the scanning width.

  A projector according to one aspect of the present invention includes a light source, a beam splitter that divides light emitted from the light source into one light and the other light, and a path of at least one of the one light and the other light. A scanning mirror having at least one mirror for changing the light, one mirror surface on which one light is incident and reflects the one light, and another mirror surface on which the other light is incident and reflects the other light It has.

  According to said structure, the same image can be simultaneously projected on two screens by one scanning mirror drive device by using both one mirror surface of a scanning mirror, and another mirror surface.

  The above-mentioned light sources include a red light source that emits red light, a green light source that emits green light, and a blue light source that emits blue light, and the combined light of red light, green light, and blue light enters the beam splitter. May be. According to this, a color image can be displayed.

  Also, after the beam splitter is a half mirror, one light passes through the half mirror and then enters one mirror, and the other light is reflected by the half-me and then reflected by at least one or more mirrors. The light may be incident on another mirror surface. According to this, the above-described projector can be realized with an extremely simple structure.

  A projector according to another aspect of the present invention includes a first light source, a second light source, a mirror surface on which light emitted from the first light source is incident, and light emitted from the second light source is incident. A first mirror that reflects the light, a first mirror that reflects the light, and a second mirror that reflects the light. 2 mirrors.

  According to said structure, two types of images can be projected on two screens using one scanning mirror drive device.

  The first light source includes a first red light source that emits first red light, a first green light source that emits first green light, and a first blue light source that emits first blue light. And the second light source includes a second red light source that emits second red light, a second green light source that emits second green light, and a second blue light source that emits second blue light. , The combined light of the first red light, the first green light, and the first blue light is incident on the surface of the scanning mirror, and the second red light, the second green light, and the second light Light synthesized with blue light may be incident on the back surface of the scanning mirror. According to this, a color image can be displayed.

Hereinafter, a projector according to an embodiment of the present invention will be described with reference to the drawings.
(Embodiment 1)
First, the projector according to the first embodiment of the present invention will be described with reference to FIGS.

  As shown in FIG. 1, the projector PJ according to the present embodiment has a light source including a red light source R, a green light source G, and a blue light source B. The projector PJ according to the present embodiment includes dichroic mirrors DM1 and DM2. Furthermore, the projector PJ of the present embodiment includes a half mirror HM, a fixed mirror FM1, a fixed mirror FM2, and a scanning mirror SM.

  The light emitted from the red light source R passes through the dichroic mirrors DM1 and DM2 and reaches the half mirror HM. However, the light emitted from the red light source R is attenuated in each of the dichroic mirrors DM1 and DM2. That is, the transmissivity of each red light source R of the dichroic mirrors DM1 and DM2 is not 100%.

  The light emitted from the green light source G is reflected by the dichroic mirror DM1. That is, the dichroic mirror DM1 is a mirror that transmits red light but reflects green light. The green light reflected by the dichroic mirror DM1 passes through the dichroic mirror DM2. However, the green light is attenuated when passing through the dichroic mirror DM2. That is, the green transmittance of the dichroic mirror DM2 is not 100%.

  The light emitted from the blue light source B is reflected by the dichroic mirror DM2. That is, the dichroic mirror DM2 is a mirror that transmits red light and green light but reflects blue light. Therefore, the light emitted from the red light source R, the light emitted from the green light source G, and the light emitted from the blue light source B are already superimposed when entering the half mirror HM.

  In the projector of the present embodiment, the control device adjusts the intensity of each of the light emitted from the red light source R, the light emitted from the green light source G, and the light emitted from the blue light source B. The color of each pixel is determined.

  Further, in the present embodiment, only a predetermined amount of light passes through the half mirror HM and reaches the mirror surface provided on the surface of the scanning mirror SM. On the other hand, light other than the predetermined amount is reflected by the half mirror HM and reaches the fixed mirror FM1. The fixed mirror FM1 reflects light toward the fixed mirror FM2. The fixed mirror FM2 reflects light toward a mirror surface provided on the back surface of the scanning mirror SM.

  That is, the two lights separated by the half mirror HM are incident on the front-side mirror surface and the back-side mirror surface of the scanning mirror SM, respectively.

  The light reflected by the mirror surface on the front side of the scanning mirror SM is emitted to the outside from the projector PJ and is incident on the screen SR1. Thus, when the scanning mirror SM is scanned, an image is formed on the screen SR1.

  On the other hand, the light reflected by the mirror surface on the back side of the scanning mirror SM reaches the screen SR2. By scanning with the scanning mirror SM, the same image as the image formed on the screen SR1 is formed on the screen SR2 at the same timing as the image is formed on the screen SR1.

  In each of the screen SR1 and the screen SR2, the same type of image is formed. The sizes of these images are the distance D1 from the mirror surface of the scanning mirror SM to the screen SR1 and the mirror surface of the scanning mirror SM to the screen SR2. Depending on the ratio to the distance D2. That is, the smaller the distance from the mirror surface of the scanning mirror SM to the screen, the smaller the image is formed on the screen. The farther the distance from the mirror surface of the scanning mirror SM is, the larger the image is formed on the screen.

  2 and 3, the scanning mirror SM is a two-dimensional scanning mirror that can freely change the inclination around the X axis and the Y axis. A substantially circular mirror surface is provided on each of the front and back surfaces of the flat scanning mirror SM. Further, the rotation axes x and y that support the circular mirror surface extend along the X axis and the Y axis, respectively. The rotation axes x and y are inserted into the bearings. In addition, the S pole and the N pole of the magnet are provided on the upper, lower, left and right sides of the scanning mirror SM. Further, a current flows through the coil or the like. Due to the magnetic force formed thereby, the two mirror surfaces of the scanning mirror SM change the inclination around the X-axis direction and the Y-axis direction, respectively.

  Scan lines on the screens SR1 and SR2 are shown in FIGS. FIG. 4 shows scanning lines when a large image is formed. On the other hand, FIG. 5 shows scanning lines when a small image is formed. In the present embodiment, scanning of the light reflected by the front and back surfaces of the scanning mirror SM driven by the same driving device is performed, so that the movement of the scanning lines on the screens SR1 and SR2 is as shown in FIG. As shown in FIG.

  Further, images shown on the screens SR1 and SR2 are shown in FIGS. As can be seen from FIGS. 6 and 7, the contents of the two images are the same, but the sizes of the images are different. As described above, if the distance from the mirror surface of the scanning mirror SM to the screen is large, a large image is formed as shown in FIG. 6, and if the distance from the mirror surface of the scanning mirror SM to the screen is small, FIG. As shown, a small image is formed.

  According to the projector of the present embodiment, it is possible to project the same type of image on two screens using one scanning mirror driving device. According to this, for example, when explaining something to a large number of viewers using a projector, a relatively large image is formed on a screen for a large number of viewers, and at the same time, A relatively small image can be formed on the screen. Therefore, the presenter can explain the viewer while viewing a small image located relatively close without viewing a large image located relatively far.

  Further, in the projector shown in FIG. 1, three light sources including a blue light source, a red light source, and a green light source are used to display a color image. The present invention is as shown in FIG. In addition, the present invention can be applied to a projector provided with only one light source L. According to this, a monotone image is formed on each of the screens SR1 and SR2.

  In the present embodiment, a half mirror is used as the beam splitter of the present invention, but any beam splitter may be used as long as one beam is divided into two. In addition, it is not the essence of the invention how the light divided into two is incident on the mirror surface on the front side and the back side of the scanning mirror SM, and may be achieved by any means. In the present embodiment, fixed mirrors FM1 and FM2 are used, but other mirrors may be used. Also, instead of changing the path of only one of the two divided lights, the path of each of the divided lights is changed so that both the front mirror surface and the back mirror surface of the scanning mirror SM are changed. It may be incident. In short, the light emitted from the same light source and divided into two light beams may be incident on the front mirror surface and the back mirror surface of the scanning mirror SM, respectively.

  In this embodiment, two mirror surfaces provided on the front and back surfaces of the plate-like body are used, but two sheets provided on each of the two outer surfaces of the V-shape. The two mirror images may be used to form two images.

(Embodiment 2)
Next, the projector PJ according to the second embodiment will be described with reference to FIGS.

  The projector PJ according to the present embodiment includes red light sources R1 and R2 that emit red light, green light sources G1 and G2 that emit green light, and blue light sources B1 and B2 that emit blue light.

  Further, the projector according to the present embodiment includes dichroic mirrors DM1, DM2, DM3, and DM4 having functions similar to the functions of the dichroic mirror described in the first embodiment. Further, the projector PJ of the present embodiment has a scanning mirror SM in which a mirror is provided on each of the front surface and the back surface. Further, the projector PJ of the present embodiment includes fixed mirrors FM1 and FM2. The light emitted from the red light source R1 passes through the dichroic mirrors DM1 and DM2 and reaches the surface of the scanning mirror SM. Further, the light emitted from the green light source G1 is reflected by the dichroic mirror DM1, passes through the dichroic mirror DM2, and reaches the surface of the scanning mirror SM. Further, the light emitted from the blue light source B1 is reflected by the dichroic mirror DM2 and reaches the surface of the scanning mirror SM.

  The light emitted from the red light source R1, the light emitted from the green light source G1, and the light emitted from the blue light source B1 are overlapped and reflected on the surface of the scanning mirror SM and reach the fixed mirror FM1. Further, the light reflected by the fixed mirror FM1 reaches the screen SR1.

  On the other hand, the light emitted from the red light source R2 passes through the dichroic mirrors DM3 and DM4 and reaches the back surface of the scanning mirror SM. The light emitted from the green light source G2 is reflected by the dichroic mirror DM3, passes through the dichroic mirror DM4, and reaches the back surface of the scanning mirror SM. Further, the light emitted from the blue light source B2 is reflected by the dichroic mirror DM4 and reaches the back surface of the scanning mirror SM.

  The light emitted from the red light source R2, the light emitted from the green light source G2, and the light emitted from the blue light source B2 are overlapped to reach the back surface of the scanning mirror SM. The light reflected by the back surface of the scanning mirror SM reaches the fixed mirror FM2. Thereafter, the light reflected by the fixed mirror FM2 reaches the screen SR2.

  The scanning mirror SM is a two-dimensional scanning mirror having the same structure as the scanning mirror of the first embodiment. Therefore, as shown in FIGS. 10 and 11, the light reflected on the surface of the scanning mirror SM and the light reflected on the back surface of the scanning mirror SM are scanned independently on the two screens. Whether the image is projected in any of the forms shown in FIGS. 10 and 11 depends on whether the scanning mirror is placed parallel to the horizontal plane and the reflected light is scanned, or the scanning mirror is placed parallel to the vertical plane and the reflected light is projected. Depends on whether to scan. In this embodiment, the scanning lines shown in FIGS. 10 and 11 are assumed to have the same locus at different positions.

  According to the projector PJ of the present embodiment, the image formed by the light incident on the mirror surface on the front side of the scanning mirror SM is different from the image formed by the light incident on the mirror surface on the back side of the scanning mirror SM. When the respective light sources are controlled, different images can be simultaneously displayed on the screens SR1 and SR2, as shown in FIGS. Therefore, these two different images can be integrated to form a single large image. According to this, a large image can be formed without increasing the swing width of the scanning mirror SM.

  The projector PJ according to the present embodiment uses a red light source, a green light source, and a blue light source to display a color image. However, when a monotone image is displayed, it is shown in FIG. Thus, a projector in which white light sources such as the light sources L1 and L2 are provided, light emitted from the light source L1 enters the surface of the scanning mirror SM, and light emitted from the light source L2 enters the back surface of the scanning mirror SM. Even so, a large image can be formed by one scanning mirror without increasing the swing width. A light source that emits light of a specific wavelength may be used instead of the white light source.

  Further, the fixed mirrors FM1 and FM2 used in each of the above embodiments may be replaced with mirrors that are controlled to change their postures. According to this, two images can be appropriately projected according to the position of the screen which projects two images.

Also in the present embodiment, two mirror surfaces provided on the front and back surfaces of the plate-like body are used, but two sheets provided on each of the two outer surfaces of the V-shape. The two mirror images may be used to form two images.

The embodiment disclosed this time should be considered as illustrative in all points and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

2 is a diagram illustrating an optical system of the projector according to Embodiment 1. FIG. It is a front view of a scanning mirror. It is the III-III sectional view taken on the line in FIG. It is a figure for demonstrating the locus | trajectory of the scanning line in case a comparatively big image is formed. It is a figure for demonstrating the locus | trajectory of the scanning line in case a relatively small image is formed. It is a figure for demonstrating that a comparatively big image is formed. It is a figure for demonstrating that a relatively small image is formed. FIG. 10 is a diagram for explaining a modification of the projector according to the first embodiment. FIG. 6 is a diagram for explaining an optical system of a projector according to a second embodiment. It is a figure for demonstrating that two images are formed along with a scanning direction. It is a figure for demonstrating that two images are formed along with the direction perpendicular | vertical to a scanning direction. It is a figure for demonstrating the case where two images are formed side by side. It is a figure for demonstrating the case where two images are formed along with lengthwise. It is a figure for demonstrating the modification of the projector of Embodiment 2. FIG.

Explanation of symbols

  R, G, B, R1, G1, B1, R2, G2, B2, L1, L2 Light source, DM1, DM2, DM3, DM4 Dichroic mirror, HM half mirror, FM1, FM2 fixed mirror, SM scanning mirror, SR1, SR2 screen.

Claims (5)

A light source;
A beam splitter that divides the light emitted from the light source into one light and the other light;
At least one mirror that changes the path of at least one of the one light and the other light; and
A projector comprising a scanning mirror having one mirror surface on which the one light is incident and reflecting the one light and another mirror surface on which the other light is incident and reflects the other light. The light source includes a red light source that emits red light, a green light source that emits green light, and a blue light source that emits blue light,
The projector according to claim 1, wherein light obtained by combining the red light, the green light, and the blue light is incident on the beam splitter. The beam splitter is a half mirror;
The one light passes through the half mirror and then enters the one mirror surface.
2. The projector according to claim 1, wherein the other light is reflected by the half-mee, then reflected by the at least one or more mirrors, and then incident on the other mirror surface. A first light source;
A second light source;
A scanning mirror having one mirror on which the light emitted from the first light source is incident and another mirror on which the light emitted from the second light source is incident;
A first mirror that receives light reflected by the one mirror surface and reflects the light;
A projector comprising: a second mirror that receives light reflected by the other mirror surface and reflects the light. The first light source includes a first red light source that emits first red light, a first green light source that emits first green light, and a first blue light source that emits first blue light,
The second light source includes a second red light source that emits second red light, a second green light source that emits second green light, and a second blue light source that emits second blue light,
The first red light, the first green light, and the first blue light combined are incident on the one mirror surface,
The projector according to claim 1, wherein light obtained by combining the second red light, the second green light, and the second blue light is incident on the other mirror surface.

Images