JP2010085472A - Image projection/imaging apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact image projection/imaging apparatus obtained by integrating an image projection apparatus and an imaging apparatus. <P>SOLUTION: The image projection/imaging apparatus 1A includes a scanning type projection part 10, a length measurement part 30 and an imaging part 40. The scanning type projection part 10 forms projection light by performing two-dimensional scanning with three color semiconductor laser beams emitted from light sources 11R, 11G and 11B. The length measurement part 30 utilizes the projection light to measure a distance to an object and the dimension of the object. The imaging part 40 automatically adjusts focus based on the measured result and photographs the object. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an image projection / imaging apparatus in which an image projection apparatus that scans light emitted from a light source and displays an image and an imaging apparatus are integrated.

  In recent years, there has been an increasing demand for downsizing image projection apparatuses. For example, it is extremely attractive that a mobile phone is equipped with an ultra-compact image projection device and a small screen of the mobile phone can be enlarged and projected so that it can be viewed “anytime and anywhere” by a large number of people regardless of business use or personal use. (See Non-Patent Document 1).

  In addition, the small image projection apparatus can use a mobile phone as an alternative to a personal computer (PC) by using the current high-speed communication technology. That is, it is a so-called thin client system in which computation processing and the like on a PC are left to a remote host computer, and data transferred by high-speed communication is received by a mobile phone and displayed on a small image projector.

  Recently, a series of exhibitions and announcements regarding this type of small image projection device have been made. For example, Microvision Co., Ltd. has shown a mobile phone size ultra-small image projection device and has attracted attention (for example, CES2008).

  There are various types of image projection apparatuses. Among them, the optical scanning type image projection apparatus forms an image by scanning while laser-modulating laser light. This optical scanning image projection apparatus can form a clear and wide color reproduction range image by superimposing laser beams of three primary colors of red, green, and blue, and uses a semiconductor laser as a light source, and a beam scanning unit By using MEMS (Mechanical Electrical Machine System), it is possible to reduce the size and power consumption.

On the other hand, Japanese Patent Application Laid-Open No. 2005-204296 discloses an imaging system including a light emitting device and a camera using laser beams of a plurality of colors as light sources.
JP-A-2005-204296 Published by Nikkei BP, "Nikkei Microdevice", (February 2007, pages 23-37)

  As described above, in recent years, a light beam scanning ultra-compact image projection apparatus has been proposed and its functional verification is progressing. In addition, small-sized imaging devices such as mobile phone terminal-attached cameras and digital cameras are widely used. However, no device that organically combines them is currently reported, and both are treated as separate devices.

  An object of the present invention is to apply a function of a light beam scanning image projection apparatus to an imaging apparatus, thereby causing the imaging apparatus to exhibit a new function.

  Another object of the present invention is to reduce the size of the image projection / imaging apparatus.

  The above and other objects and novel features of the present invention will be apparent from the description of this specification and the accompanying drawings.

  Of the inventions disclosed in the present application, the outline of typical ones will be briefly described as follows.

In order to achieve the above object, the image projection / imaging apparatus of the present invention has the following three functions.
(1) The scanning light beam of the light beam scanning ultra-small image projector is used for illumination of the imaging device.
(2) The distance to the measurement object and the dimension of the measurement object are measured using the scanning light beam of the light beam scanning ultra-small image projector.
(3) The focus of the imaging device is automatically adjusted using the length measurement result of (2).

  More specifically, the image projection / imaging device of the present invention is characterized by having the following configuration.

1. A plurality of light sources having different emission wavelengths, including a semiconductor laser that oscillates in blue, green, and red, or a second harmonic element that is excited by the semiconductor laser;
A first optical system that condenses a plurality of light beams generated from the light source in one axis;
A second optical system for emitting the scanned uniaxial light beam to the outside;
A light beam scanning image projection unit that has a control system for synchronizing and controlling the output of the light source and scanning means based on an image signal, and that emits the scanned light beam of one axis to the outside;
In an image projection / imaging apparatus comprising an imaging unit that images a subject,
A beam diameter of light from the plurality of light sources is adjusted by the second optical system and used for illumination for imaging the subject.

2. In the image projection / imaging device according to 1 above,
(1) a mechanism that uses light of any color formed by adjusting light emission intensities from light sources having different light emission wavelengths for illumination for imaging the subject;
(2) a mechanism for illuminating a specific area of the subject using the control system;
(3) A mechanism that uses the control system to irradiate a light beam for the illumination in synchronization with a time for imaging the subject;
Among these, it has at least one mechanism.

3. A plurality of light sources having different emission wavelengths, including a semiconductor laser that oscillates in blue, green, and red, or a second harmonic element that is excited by the semiconductor laser;
A first optical system that condenses a plurality of light beams generated from the light source in one axis;
A second optical system for emitting the scanned uniaxial light beam to the outside;
A light beam scanning image projection unit that has a control system for synchronizing and controlling the output of the light source and scanning means based on an image signal, and that emits the scanned light beam of one axis to the outside;
In an image projection / imaging apparatus comprising an imaging unit that images a subject,
An array light receiving element having a plurality of independent light receiving surfaces;
A mechanism for manually operating the control system;
A calculation function for calculating a distance to the length measurement object by emitting light from the light source at a predetermined angle by the control system and receiving reflected light from the length measurement object by the array light receiving element; It is characterized by that.

4). In the image projection / imaging apparatus of 3,
The beam scanning system scans light from the light source according to the dimension of the length measurement object, and has a calculation function for calculating the size of the length measurement object from the scanning angle and the distance to the length measurement object. It is characterized by doing.

5). In the image projection / imaging apparatus of 3,
It has a function of focusing the subject imaged by the imaging unit from the distance to the length measurement object.

  6). The image projection / imaging device according to any one of 1 to 6 is characterized in that the image projection / imaging device is built in a mobile phone terminal.

  Among the inventions disclosed in the present application, effects obtained by typical ones will be briefly described as follows.

  A compact image projection / imaging device in which the image projection device and the imaging device are integrated can be realized.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Note that components having the same function are denoted by the same reference symbols throughout the drawings for describing the embodiments, and the repetitive description thereof will be omitted. Also, in the following embodiments, the description of the same or similar parts will not be repeated in principle unless particularly necessary.

  FIG. 1 is a configuration diagram illustrating an image projection / imaging apparatus according to the present embodiment. The image projection / imaging apparatus 1A according to the present embodiment includes a scanning projection unit 10, a length measurement unit 30, and an imaging unit 40.

  First, the configuration of the scanning projection unit 10 will be described. The scanning projection unit 10 includes a light source 11B made of a blue laser, a light source 11G made of a green laser, and a light source 11R made of a red laser. These three light sources 11R, 11G, and 11B are arranged side by side in one direction. In this example, three-color semiconductor lasers (blue laser, green laser, and red laser) are used as a plurality of light sources (11R, 11G, and 11B) having different wavelengths, but the second harmonic excited by the semiconductor laser. A plurality of light sources having different emission wavelengths including the element may be used.

  In the vicinity of the light source 11B made of a blue laser, an optical system including a condenser lens 12b for condensing the blue laser light emitted from the light source 11B uniaxially and a dielectric film filter 13b is disposed. The dielectric film filter 13b has a property of reflecting 90% or more of the blue laser light, and is disposed at an angle of 45 ° with respect to the traveling direction of the blue laser light transmitted through the condenser lens 12b. Therefore, most of the blue laser light (90% or more) transmitted through the condenser lens 12b is reflected by the surface of the dielectric film filter 13b and its traveling direction is converted by 90 °.

  In the vicinity of the light source 11G composed of a green laser disposed adjacent to the light source 11B, an optical system comprising a condenser lens 12g for condensing the green laser light emitted from the light source 11G uniaxially and a dielectric film filter 13g. Is arranged. The dielectric film filter 13g has a property of transmitting 90% or more of the blue laser light and reflecting 90% or more of the green laser light. The dielectric film filter 13g is disposed on the optical path of the blue laser light reflected by the surface of the dielectric film filter 13b, and at an angle of 45 ° with respect to the traveling direction of the green laser light transmitted through the condenser lens 12g. Has been placed. Accordingly, most (90% or more) of the blue laser light reflected by the surface of the dielectric filter 13b passes through the dielectric filter 13g and travels straight. Further, most of the green laser light (90% or more) transmitted through the condensing lens 12g is reflected by the surface of the dielectric film filter 13g, the traveling direction thereof is converted by 90 °, and the blue laser beam transmitted through the dielectric film filter 13g. Go straight alongside the light.

  In the vicinity of the light source 11R made of a red laser disposed adjacent to the light source 11G, an optical system comprising a condenser lens 12r for condensing the red laser light emitted from the light source 11R uniaxially and a dielectric film filter 13r. Is arranged. The dielectric film filter 13r has a property of transmitting about 80% of blue laser light and green laser light and transmitting about 20% of red laser light. The dielectric film filter 13r is disposed on the optical path of the blue laser light transmitted through the dielectric film filter 13g and the green laser light reflected from the surface of the dielectric film filter 13g, and is a red laser transmitted through the condenser lens 12r. It arrange | positions at an angle of 45 degrees with respect to the advancing direction of light. Accordingly, about 80% of the blue laser light transmitted through the dielectric film filter 13g and about 80% of the green laser light reflected from the surface of the dielectric film filter 13g pass through the dielectric film filter 13r and go straight. Further, about 80% of the red laser light transmitted through the condenser lens 12r is reflected by the surface of the dielectric film filter 13r and its traveling direction is converted by 90 °, and the blue laser light and green laser light transmitted through the dielectric film filter 13r. Go straight alongside the light.

  The blue laser light and green laser light transmitted through the dielectric film filter 13r and the red laser light reflected from the surface of the dielectric film filter 13r are incident on the scanning mirror. The scanning mirror 14 is composed of, for example, a biaxial drive MEMS element. Moreover, the scanning mirror 14 can also be comprised combining a uniaxial drive MEMS element. The three colors of laser light incident on the scanning mirror 14 are scanned two-dimensionally to form projection light. The scanning speed here is, for example, 60 Hz / screen (frame). The projection light scanned by the scanning mirror 14 is emitted to the outside through the lens 15 and then enlarged and projected as a full-color image on the surface of an object such as a screen (not shown).

  On the other hand, the blue laser light and green laser light reflected by the surface of the dielectric film filter 13r and the red laser light transmitted through the dielectric film filter 13r are incident on the photodetector 16. Further, the control unit 17 connected to the light detector 16 is based on the output signals of the three colors of laser light detected by the light detector 16 and the image signal 18, and then the light sources 11B and 11G via the laser control unit 19. , 11R, and the operation of the scanning mirror 14 via the scanning mirror controller 20 is controlled.

  FIG. 2 is a graph for explaining the operation of the scanning projection unit 10. The horizontal axis indicates time, and the vertical axes B, G, and R indicate a light source 11B made of a blue laser, a light source 11G made of a green laser, and a red color. Each output of the light source 11R made of a laser is shown.

  Times a1 and a2 are times for image projection. By adjusting the output of the light sources (11B, 11G, 11R) and superimposing the three colors, any color can be created at any time. The time b1 is a time for detecting outputs of three colors by the photodetector 16. During this time, the light sources (11B, 11G, and 11R) are individually operated. By performing such time division, it becomes possible to detect the outputs of a plurality of light sources (11B, 11G, 11R) with a single photodetector 16.

Next, a procedure for projecting a full color image is shown below.
(1) The relationship between the output of the light source (11B, 11G, 11R) and the drive current is obtained by the light detection shown in FIGS.
(2) The control unit 17 converts the two-dimensional image signal into position information and color information.
(3) Based on the relationship obtained in (1), the output of the light sources (11B, 11G, 11R) is adjusted corresponding to the color position information in (2).
(4) According to the positional information of (2), the scanning mirror 14 is two-dimensionally scanned in a predetermined step to project a two-dimensional full-color image to the outside.

  Here, it is possible to automatically operate the photodetector 16 at regular time intervals, and to automatically operate the photodetector 16 at the start of the operation of the scanning projection unit 10. Convenience can be improved.

  The image projection / imaging apparatus 1A according to the present embodiment uses projection light scanned by the scanning mirror 14 and emitted to the outside via the lens 15 for illumination of the imaging apparatus.

  FIG. 3A shows an example in which the projection light emitted through the lens 15 is parallel light. In order to make the projected image clear, the light intensity of the parallel light is relatively strong (for example, several tens of mW), and there is a possibility of causing trouble if it enters the eyes when photographing a person. Therefore, in this embodiment, the beam diameter is enlarged by the following method and used for illumination. 3B is an example in which the beam diameter is enlarged by bringing the lens 15 closer to the scanning mirror 14, and FIG. 3C is an example in which the beam diameter is enlarged by adding lenses 21 and 22 newly. It is. As described above, the illumination required for the imaging device can be obtained by applying the above-described device to the light emitting portion including the scanning mirror 14 and the lens 15.

  An example of the shape of the projection light used for illumination of the imaging device is shown in FIG. FIG. 4A shows an example in which illumination of an arbitrary size can be emitted to an arbitrary place by adjusting the beam diameter of the projection light without driving the scanning mirror 14. The adjustment of the beam diameter is performed by the control unit 17 shown in FIG. FIG. 4B shows an example in which a rectangular illumination pattern is formed by driving the scanning mirror 14. The beam diameter is 3 cm, for example. Further, by registering a pattern in the control unit 17 in advance, it is possible to form an illumination pattern having an arbitrary shape such as a circular shape or a heart shape.

  Next, a method for adjusting the color of projection light used for illumination of the imaging apparatus is shown in FIG. In the present embodiment, since the three color light sources (11B, 11G, and 11R) are used, the color adjustment of the illumination is easy. FIG. 5A is an example in which white illumination is obtained using all three color light sources (11B, 11G, and 11R). FIG. 5B is an example of obtaining light blue illumination using the blue light source 11B and the green light source 11G. In FIG. 5C, a green light source 11G is used in the first half of one frame, a red light source 11R is used in the second half, and the scanning mirror 14 is further operated so that half is green and the other half is red. This is an example.

  FIG. 5 also shows the opening and closing time of the shutter when shooting a still image. Thus, by synchronizing the color adjustment and the opening / closing time of the shutter, power consumption due to illumination can be saved. Moreover, it is also possible to obtain illumination by combining the methods described in FIGS. 3 to 5, and it is also possible to use a pattern of an image projected on a surface such as a screen for illumination. Furthermore, the same subject can be photographed again using an image obtained by photographing the subject as illumination.

  In the image projection / imaging apparatus 1A according to the present embodiment, the length measurement unit 30 uses the illumination to measure the distance to the measurement object and the dimensions of the measurement object. And based on this measurement result, a focus is automatically adjusted in the imaging part 40, and a target object is image | photographed.

  First, a method for obtaining the distance to the object will be described with reference to FIG. In order to simplify the explanation, only the array type light receiving element 31 for position detection provided in the length measuring unit 30, the scanning mirror 14, and the illumination (LD) are shown in FIG. As the array type light receiving element 31, for example, a CCD element having an interval of 1 mm and 128 elements can be used.

  First, illumination (LD) is irradiated to the measurement object 32, and the address of the CCD element that obtains the maximum intensity by receiving the reflected light from the object 32 by the CCD element of the array type light receiving element 31 is obtained. Next, the scanning mirror 14 is operated to irradiate the object 32 with illumination (LD), and the reflected light at different scanning mirror angles (Φ1, Φ2) is received by the CCD element of the array type light receiving element 31 to obtain the maximum intensity. The address of the CCD element that obtains is obtained. Then, the distance (L) to the object 32 is determined by the principle of triangulation from the relationship between the deviation amount (D) of the maximum peak position on the CCD element and the scanning mirror angle (Φ). Although the distance (L) can be obtained with high accuracy by performing the above operation at least twice, it is possible to detect the distance with high accuracy by the least square method by continuously changing the scanning mirror 14.

  Next, as shown in FIG. 6B, the scanning mirror 14 is adjusted so that illumination (LD) coincides with both ends of the object 32. Then, the dimension (W) of the object 32 is obtained from the scanning mirror angle (Φ) at this time and the distance (L) to the object 32 obtained in FIG.

  FIG. 7 is a configuration diagram illustrating an automatic focusing mechanism of the imaging unit 40. In order to simplify the explanation, the scanning projection unit 10 of FIG. 1 is shown in a simplified manner in FIG.

  The imaging unit 40 includes lenses 41, 42, and 43, a CCD element 44, a shutter (not shown), and the like. The imaging unit 40 adjusts the positions of the lenses 41, 42, and 43 based on the distance (L) and the dimension (W) to the object 32 measured by the length measuring unit 30 to adjust the focus. These operations are performed by the control unit 17 of the scanning projection unit 10. FIG. 8 is a timing chart showing the time course of the above operation. When the shutter is pushed, measurement of the distance (L) and dimension (W), automatic focusing by the imaging unit 40, and opening and closing of the shutter are automatically performed as a series of scans. Here, the case of white illumination in which three color light sources (11R, 11G, and 11B) are simultaneously irradiated is shown.

  As mentioned above, the invention made by the present inventor has been specifically described based on the embodiment. However, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention. Needless to say.

  In the image projection / imaging apparatus of the present invention, the light source is composed of a semiconductor laser element, and the scanning system is composed of a MEMS element, so that the scanning projection unit can be miniaturized. Therefore, for example, as shown in FIG. 9, by incorporating the image projection / imaging device of the present invention in the mobile phone terminal 50 with a camera, an ultra-compact image projection / imaging device can be realized.

  In the above-described embodiment, the image projection / imaging apparatus including the scanning projection unit, the length measurement unit, and the imaging unit has been described. However, the configuration including the normal projection unit, the length measurement unit, and the imaging unit, or the projection A configuration specialized for a part of the function, such as a configuration including a unit and an imaging unit, is also possible.

  The present invention can be applied to an image projection / imaging apparatus in which the image projection apparatus is integrated with the imaging apparatus.

It is a block diagram of the image projection and imaging device which is one embodiment of this invention. It is a graph explaining operation | movement of a scanning projection part. (A), (b), (c) is explanatory drawing which shows the method of obtaining illumination light from the projection light formed in the scanning projection part. (A), (b) is explanatory drawing which shows the example of a shape of illumination light. (A), (b), (c) is explanatory drawing which shows the color adjustment method of illumination light. (A) is a figure explaining the method of calculating | requiring the distance to a target object in a length measuring part, (b) is a figure explaining the method of calculating | requiring the dimension of a target object in a length measuring part. It is a block diagram which shows the automatic focus mechanism of an imaging part. It is a timing diagram which shows the time course of operation performed in an imaging part. It is explanatory drawing of embodiment which incorporated the image projection and imaging device of this invention in the mobile telephone terminal.

Explanation of symbols

1A Image Projection / Imaging Device 10 Scanning Projectors 11B, 11G, 11R Light Sources 12b, 12g, 12r Condensing Lenses 13b, 13g, 13r Dielectric Film Filter 14 Scanning Mirror 15 Lens 16 Photodetector 17 Controller 18 Image Signal 19 Laser Control unit 20 Scanning mirror control unit 21, 22 Lens 30 Measuring unit 31 Arrayed light receiving element 32 Object 40 Imaging unit 41, 42, 43 Lens 44 CCD element

Claims (11)

An image projection / imaging apparatus comprising a scanning projection unit, a length measurement unit, and an imaging unit,
The scanning projection unit includes:
A light source;
A first optical system that condenses light emitted from the light source uniaxially;
A scanning system that forms a projection light by two-dimensionally scanning the light focused on the one axis;
A second optical system that emits the scanned projection light to the outside and enlarges and projects it as an image on the surface of the object;
A controller for controlling the output of the light source and the scanning system based on an image signal,
The length measuring unit has a function of measuring a distance to an object and a dimension of the object using the projection light formed by the scanning projection unit,
The imaging unit has a function of adjusting the focal point based on the distance to the object and the size of the object obtained by the length measuring unit, and photographing the object. Image projection / imaging device.   2. The image projection / imaging apparatus according to claim 1, wherein the light source includes a plurality of semiconductor lasers that respectively oscillate in blue, green, and red.   The image projection / imaging apparatus according to claim 1, wherein the light source is light having a plurality of emission wavelengths including a second harmonic element excited by a semiconductor laser.   The image projection / imaging apparatus according to claim 1, wherein the scanning system of the scanning projection unit includes a MEMS element.   2. The image projection / projection device according to claim 1, wherein the length measuring unit includes an array type light receiving element including a plurality of CCD elements that receive reflected light of the projection light irradiated on the object. Imaging device. A mechanism that uses light of any color formed by adjusting light emission intensities from a plurality of the light sources for illumination for imaging the object;
A mechanism for illuminating a specific area of the object using the scanning system;
The image projection / imaging apparatus according to claim 2, further comprising at least one mechanism among mechanisms for illuminating the object in synchronization with a time for photographing the object using the control unit.   2. The image projection / imaging apparatus according to claim 1, wherein the image projection / imaging apparatus is built in a camera-equipped mobile phone terminal. An image projection / imaging apparatus comprising a scanning projection unit, a length measurement unit, and an imaging unit,
The scanning projection unit includes:
A light source;
A first optical system that condenses light emitted from the light source uniaxially;
A scanning system that forms a projection light by two-dimensionally scanning the light focused on the one axis;
A second optical system that emits the scanned projection light to the outside and enlarges and projects it as an image on the surface of the object;
A controller for controlling the output of the light source and the scanning system based on an image signal,
The length measuring unit has a function of measuring a distance to an object and a dimension of the object using the projection light formed by the scanning projection unit,
An array light receiving element having a plurality of independent light receiving surfaces;
A mechanism for manually operating the scanning system;
A calculation function for calculating a distance to the object by emitting light from the light source at a predetermined angle by the scanning system and receiving reflected light from the object by the array light receiving element; An image projection / imaging apparatus characterized by that.   The scanning system scans the light from the light source in accordance with the size of the object, and has a calculation function for calculating the size of the object from the scanning angle and the distance to the object. The image projection / imaging device according to claim 8.   The image projection / imaging apparatus according to claim 8, further comprising a function of focusing the object to be imaged by the imaging unit based on a distance to the object.   9. The image projection / imaging apparatus according to claim 8, wherein the image projection / imaging apparatus is built in a mobile phone terminal with a camera.

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