JP2011107237A - Image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an image forming apparatus that facilitates an observer to recognize the existence of an image displayed in a drawing area by varying the image displayed in the drawing area depending on existence/inexistence of the observer on the drawing area which displays the image. <P>SOLUTION: The image forming apparatus includes: a projector 2 which is so configured to plot an image by scanning laser light LL on the drawing area 91 formed on a display face 9; a man-detective sensor (man detection unit) 6 which detects the existence/inexistence of a man in the drawing area 91; and a control means 8 which controls the driving of the projector 2 so as to vary the image or the image pattern plotted in the drawing area 91 depending on whether the man-detective sensor 6 detects the existence of the man in the drawing area 91. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an image forming apparatus.

A projector is used as an instrument that projects light onto a surface (drawing area) such as a screen and displays a desired image on the screen. As such a projector, a projector using an optical scanner capable of scanning light one-dimensionally or two-dimensionally is widely known (for example, see Patent Document 1).
In the projector described in Patent Document 1, when the x axis and the y axis that are orthogonal to each other are set, the movable plate having the light reflecting portion rotates around the x axis, and the movable having the light reflecting portion. The plate has a second optical scanner that rotates about the y-axis, and a light source device that emits light such as a laser. In such a projector, the light emitted from the light source device is scanned by the first optical scanner, and the scanned light is further scanned by the second optical scanner, whereby the light is scanned two-dimensionally on the screen. A desired image is displayed.

Recently, there are cases where a screen is placed on the floor and an image is displayed on the screen, or an image is directly displayed on the floor without scratching the screen. In such a case, the observer can freely pass on the screen. In such a case, with the projector described in Patent Document 1, even if an image can be displayed on the screen, the image to be displayed cannot be changed according to the presence or absence of a person on the screen.
For this reason, the projector disclosed in Patent Document 1 has a problem in that an image that is easily recognized by humans cannot be displayed on a screen.

JP 2008-116668 A

  An object of the present invention is to recognize an image displayed in the drawing area by changing the image displayed in the drawing area depending on whether or not the person exists on the drawing area displaying the image. An object of the present invention is to provide an image forming apparatus that can be easily provided.

Such an object is achieved by the present invention described below.
An image forming apparatus of the present invention includes a projector configured to draw an image by scanning light rays in a drawing area formed on a display surface;
A human sensor for detecting whether a human is present in the drawing area;
Control means for controlling driving of the projector so as to change an image or an image pattern drawn in the drawing area depending on whether the human sensor detects the presence of a person in the drawing area or not. It is characterized by having.
This makes it easier for the human to recognize the image displayed in the drawing area by changing the image displayed in the drawing area depending on whether or not a person is present on the drawing area in which the image is displayed. An image forming apparatus capable of performing the above can be provided.

In the image forming apparatus according to the aspect of the invention, when the human sensor detects the presence of a human in the drawing area, the control unit does not detect the human presence in the drawing area. It is preferable to control the driving of the projector so that an image that can be easily recognized by the human being is drawn in the drawing area.
This makes it easy for a person who has entered the drawing area to recognize the image drawn in the drawing area. In addition, a person who has entered the drawing area is surprised, interested and interested in the images that have changed due to his / her intrusion, and the image changes in conjunction with his / her actions. It is possible to easily recognize the image drawn in the area.
In the image forming apparatus according to the aspect of the invention, when the human sensor detects the presence of a person in the drawing area, the control unit can urge the person in the drawing area to be in danger. It is preferable to control the driving of the projector so as to draw an image.
Thereby, the effect of the image forming apparatus is more remarkably exhibited.

In the image forming apparatus of the present invention, the projector includes a light emitting unit that emits a laser,
A movable plate provided with a light reflecting portion for reflecting the laser emitted from the light emitting portion is provided so as to be rotatable in at least one direction or two directions orthogonal to each other, and the laser reflected by the light reflecting portion by the rotation It is preferable to have an optical scanner that scans the display surface.
Thereby, the configuration of the projector becomes relatively simple.
In the image forming apparatus according to the aspect of the invention, it is preferable that the projector also serves as the human sensor.
Thereby, the configuration of the image forming apparatus becomes relatively simple.

In the image forming apparatus of the present invention, the human sensor detects a person existing in the drawing area based on the laser light emitted from the light emitting unit and reflected by the person existing in the drawing area. It is preferable to detect.
Thereby, the presence or absence of a human being present in the drawing area can be detected more reliably.
In the image forming apparatus according to the aspect of the invention, the human sensor is provided in the middle of the optical path between the light emitting unit and the light reflecting unit or at a branched position, and is reflected by the drawing region or the human and reflected again by the light. A light receiving unit that receives light returned to the reflecting unit, a time difference calculating unit that calculates a time difference between a timing at which light is emitted from the light emitting unit and a timing at which the light is received by the light receiving unit, and the time difference It is preferable to have a detection unit that detects the presence of a person in the drawing area based on a calculation result by the calculation unit.
Thereby, the configuration of the human sensor becomes relatively simple.

In the image forming apparatus according to the aspect of the invention, the human sensor is provided in the middle of the optical path between the light emitting unit and the light reflecting unit or at a branched position, and is reflected on the drawing region and again on the light reflecting unit. It is preferable to have a detection unit that detects the presence of a person in the drawing area based on the light intensity detected by the light receiving unit that receives the returned light.
Thereby, the presence or absence of a human being present in the drawing area can be detected more reliably.

In the image forming apparatus according to the aspect of the invention, it is preferable that the projector includes a distortion correction unit that corrects distortion of an image displayed on the display surface.
Thereby, an image without distortion can be drawn in the drawing area.
In the image forming apparatus of the present invention, it is preferable that the display surface is a floor surface.
Thereby, a pedestrian walking while looking forward or slightly below (that is, a pedestrian walking in a normal walking posture) can more reliably recognize the image drawn in the drawing area.

1 is a diagram illustrating a first embodiment of an image forming apparatus of the present invention. FIG. 2 is a block diagram of the image forming apparatus illustrated in FIG. 1. It is a block diagram of the projector shown in FIG. FIG. 4 is a partial cross-sectional perspective view of the optical scanner shown in FIG. 3. FIG. 5 is a cross-sectional view illustrating driving of the optical scanner shown in FIG. 4. It is a block diagram which shows the distortion correction means, the optical scanning part, and light source unit of the projector shown in FIG. FIG. 4 is a diagram (a is a side view, and b is a front view) for explaining the operation of the projector shown in FIG. 3. 4 is a graph showing a deflection angle (change in deflection angle with time) of a movable plate of the optical scanner (main scanning optical scanner) during operation of the projector shown in FIG. 3. 4 is a graph showing an angle (change in angle with time) of a movable plate of an optical scanner (sub-scanning optical scanner) during operation of the projector shown in FIG. 3. It is a figure (a is a side view and b is a front view) which shows the modification of the projector shown in FIG. 3, and its operation | movement. It is a figure which shows an example of the image which the projector shown in FIG. 2 draws in a drawing area. It is a figure explaining arrangement | positioning of an image forming apparatus. It is a typical plane which shows the optical scanner which the projector with which the image forming apparatus which concerns on 2nd Embodiment of this invention is provided has. It is the BB sectional view taken on the line in FIG. It is a block diagram which shows the voltage application means of the drive means with which the optical scanner shown in FIG. 13 is provided. It is a figure which shows an example of the voltage which generate | occur | produces in the 1st voltage generation part shown in FIG. 15, and a 2nd voltage generation part. FIG. 10 is a diagram (a is a side view, and b is a front view) for explaining an operation of a projector included in an image forming apparatus according to a second embodiment of the present invention.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of an image forming apparatus of the invention will be described with reference to the accompanying drawings.
<First Embodiment>
1 is a diagram illustrating a first embodiment of an image forming apparatus according to the present invention, FIG. 2 is a block diagram of the image forming apparatus illustrated in FIG. 1, FIG. 3 is a configuration diagram of a projector illustrated in FIG. 2, and FIG. 3 is a partial sectional perspective view of the optical scanner shown in FIG. 3, FIG. 5 is a sectional view for explaining driving of the optical scanner shown in FIG. 4, and FIG. 6 is a distortion correcting means, an optical scanning unit and a light source of the projector shown in FIG. FIG. 7 is a block diagram showing the unit, FIG. 7 is a diagram for explaining the operation of the projector shown in FIG. 3 (a is a side view, b is a front view), and FIG. 8 is in operation of the projector shown in FIG. FIG. 9 is a graph showing the deflection angle (change in the deflection angle with time) of the movable plate of the optical scanner (main scanning optical scanner). FIG. 9 is an optical scanner during operation of the projector shown in FIG. ) Movable plate angle (change in angle over time) FIG. 10 is a diagram showing a modification of the projector shown in FIG. 3 and its operation (a is a side view, b is a front view), and FIG. 11 is drawn in the drawing area by the projector shown in FIG. FIG. 12 is a diagram illustrating an example of an image, and FIG. 12 is a diagram illustrating an arrangement of the image forming apparatus. In the following, for convenience of explanation, the upper side in FIGS. 4, 5, 7, 10, and 12 is “upper”, the lower side is “lower”, the right side is “right”, and the left side is “left”. Say.

  An image forming apparatus 1 shown in FIG. 1 is an apparatus that draws (displays) an image such as a still image or a moving image in a drawing area 91 formed on a floor surface (display surface) 9. Thus, the following effects can be exhibited by setting the display surface 9 to the floor surface. In other words, a pedestrian or the like usually walks while looking forward or slightly below (the floor in front of Yuna). Therefore, by setting the display surface 9 to the floor surface, the pedestrian can be more surely recognized the image drawn in the drawing area 91 formed on the display surface 9.

The shape of the drawing area 91 is not particularly limited, and may be a square, a rectangle, a circle, an irregular shape, or the like. However, for convenience of explanation, the drawing area 91 having a rectangle will be described as a representative.
In the present embodiment, the image forming apparatus 1 draws an image in the drawing area 91 formed on the floor surface 9, but is not limited to this. For example, the image forming apparatus 1 draws on the surface of the screen drawn on the floor surface 9. A region may be formed. In this case, the constituent material of the screen is not particularly limited. For example, polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyamide, acrylic resin, ABS resin, fluorine resin, epoxy resin, silicone resin, or these are mainly used. And a copolymer, a blend, a polymer alloy, and the like, and one or more of them can be used in combination.
In the example of FIG. 1, such an image forming apparatus 1 is provided (fixed) on a ceiling positioned vertically above the drawing area 91. Further, the image forming apparatus 1 can be placed on the wall surface positioned in the vertical direction of the drawing area 91 instead of the ceiling, and can be drawn on the floor surface 9 therefrom.

  As shown in FIG. 2, the image forming apparatus 1 includes a projector 2 that scans light in a drawing area 91 and draws an image, and a control unit 8 that controls driving of the projector 2. As shown in FIG. 3, the projector 2 includes a light source unit (light emitting unit) 3 that emits light, a light scanning unit 4 that scans light emitted from the light source unit 3 with respect to the drawing region 91, and a drawing region 91. A distortion correction unit 5 that corrects distortion (trapezoid correction) of an image drawn on the human body, and a human detection unit (human sensor) 6 that detects the presence or absence of a person existing in the drawing area 91.

The light source unit 3 includes laser light sources 31r, 31g, and 31b for the respective colors, collimator lenses 32r, 32g, and 32b and dichroic mirrors 33r, 33g, and 33b provided corresponding to the laser light sources 31r, 31g, and 31b for the respective colors. I have.
Further, as shown in FIG. 6, the laser light sources 31r, 31g, and 31b for the respective colors have drive circuits 310r, 310g, and 310b, a red light source 320r, a green light source 320g, and a blue light source 320b, respectively. As shown in FIG. 3, red, green, and blue laser beams RR, GG, and BB are emitted. The laser beams RR, GG, and BB are emitted in a modulated state corresponding to drive signals transmitted from a light source modulation unit 54 (to be described later) of the distortion correction unit 5, and collimator lenses 32r that are collimating optical elements, respectively. The beams are collimated by 32g and 32b to form a thin beam.
The dichroic mirrors 33r, 33g, and 33b have characteristics of reflecting the red laser beam RR, the green laser beam GG, and the blue laser beam BB, respectively, and combine the laser beams RR, GG, and BB of the respective colors into one laser beam. (Light) LL is emitted.

  A collimator mirror can be used in place of the collimator lenses 32r, 32g, and 32b. In this case as well, a narrow beam of parallel light beams can be formed. Further, when parallel light beams are emitted from the laser light sources 31r, 31g, and 31b of the respective colors, the collimator lenses 32r, 32g, and 32b can be omitted. Further, the laser light sources 31r, 31g, and 31b can be replaced with light sources such as light emitting diodes that generate similar light beams.

  Further, the order of the laser light sources 31r, 31g, and 31b, the collimator lenses 32r, 32g, and 32b, and the dichroic mirrors 33r, 33g, and 33b in FIG. 3 is merely an example, and combinations of the colors (red indicates the laser light source 31r). , Collimator lens 32r, dichroic mirror 33r, green is laser light source 31g, collimator lens 32g, dichroic mirror 33g, blue is laser light source 31b, collimator lens 32b, dichroic mirror 33b) and the order is freely set it can. For example, a combination of blue, red, and green is also possible in the order closer to the optical scanning unit 4.

Next, the optical scanning unit 4 will be described.
The optical scanning unit 4 scans (main scans) the laser beam LL emitted from the light source unit 3 in the first direction (longitudinal direction of the drawing region 91) with respect to the drawing region 91, and also scans in the first direction. The scanning is performed two-dimensionally by scanning (sub-scanning) in the second direction (direction orthogonal to the first direction) at a slower scanning speed.

  The optical scanning unit 4 determines the angle (behavior) of the optical scanner 41 that scans the laser light LL emitted from the light source unit 3 in the first direction with respect to the drawing region 91 and a movable plate 411a (to be described later) of the optical scanner 41. An angle detecting means (behavior detecting means) 43 for detecting, an optical scanner 42 for scanning the laser light LL emitted from the light source unit 3 in the second direction with respect to the drawing region 91, and a movable plate 421a (to be described later) of the optical scanner 42. Angle detecting means (behavior detecting means) 44 for detecting the angle (behavior).

Hereinafter, the configuration of the optical scanners 41 and 42 will be described. Since the optical scanners 41 and 42 have the same configuration, the optical scanner 41 will be described below as a representative, and the optical scanner 42 will be described. Omitted.
As shown in FIG. 4, the optical scanner 41 is a so-called one-degree-of-freedom vibration system, and includes a base 411, a counter substrate 413 provided to face the lower surface of the base 411, a base 411, a counter substrate 413, and the like. And a spacer member 412 provided therebetween.

The base 411 includes a movable plate 411a, a support portion 411b that rotatably supports the movable plate 411a, and a pair of connecting portions 411c and 411d that connect the movable plate 411a and the support portion 411b.
The movable plate 411a has a substantially rectangular shape in plan view. On the upper surface of the movable plate 411a, a light reflecting portion (mirror) 411e having light reflectivity is provided. The surface (upper surface) of the light reflecting portion 411e constitutes a reflecting surface that reflects light. The light reflecting portion 411e is made of a metal film such as Al or Ni, for example. A permanent magnet 414 is provided on the lower surface of the movable plate 411a.
The support portion 411b is provided so as to surround the outer periphery of the movable plate 411a in a plan view of the movable plate 411a. That is, the support part 411b has a frame shape, and the movable plate 411a is located inside thereof.

The connecting portion 411c connects the movable plate 411a and the support portion 411b on the left side of the movable plate 411a, and the connecting portion 411d connects the movable plate 411a and the support portion 411b on the right side of the movable plate 411a. Yes.
Each of the connecting portions 411c and 411d has a longitudinal shape. Further, each of the connecting portions 411c and 411d can be elastically deformed. The pair of connecting portions 411c and 411d are provided coaxially with each other, and the movable plate 411a is located with respect to the support portion 411b around this axis (hereinafter referred to as “rotation center axis J1”). Rotate.

  Such a base 411 is made of, for example, silicon as a main material, and a movable plate 411a, a support portion 411b, and connection portions 411c and 411d are integrally formed. As described above, by using silicon as a main material, it is possible to realize excellent rotation characteristics and to exhibit excellent durability. Further, fine processing (processing) is possible, and the optical scanner 41 can be downsized.

The spacer member 412 has a frame shape, and its upper surface is joined to the lower surface of the base 411. The spacer member 412 is substantially equal to the shape of the support portion 411b in the plan view of the movable plate 411a. Such a spacer member 412 is made of, for example, various glasses, various ceramics, silicon, SiO ₂ or the like.
The method for joining the spacer member 412 and the base 411 is not particularly limited. For example, the spacer member 412 may be joined via another member such as an adhesive, or anodic joining may be performed depending on the constituent material of the spacer member 412. It may be used.
Similar to the spacer member 412, the counter substrate 413 is made of, for example, various kinds of glass, silicon, SiO ₂ or the like. A coil 415 is provided on the upper surface of the counter substrate 413 and on a portion facing the movable plate 411a.

The permanent magnet 414 has a plate bar shape and is provided along the lower surface of the movable plate 411a. Such a permanent magnet 414 is magnetized (magnetized) in a direction orthogonal to the rotation center axis J1 in a plan view of the movable plate 411a. That is, the permanent magnet 414 is provided such that a line segment connecting both poles (S pole and N pole) is orthogonal to the rotation center axis J1.
The permanent magnet 414 is not particularly limited, and for example, a neodymium magnet, a ferrite magnet, a samarium cobalt magnet, an alnico magnet, or the like can be used.

The coil 415 is provided so as to surround the outer periphery of the permanent magnet 414 in the plan view of the movable plate 411a.
Further, the optical scanner 41 includes a voltage applying unit 416 that applies a voltage to the coil 415. The voltage application unit 416 is configured to be able to adjust (change) each condition such as the voltage value and frequency of the voltage to be applied. The voltage applying unit 416, the coil 415, and the permanent magnet 414 constitute a driving unit 417 that rotates the movable plate 411a.

A predetermined voltage is applied from the voltage applying unit 416 to the coil 415 under the control of the distortion correcting unit 5, and a predetermined current flows.
For example, when an alternating voltage is applied from the voltage application unit 416 to the coil 415 under the control of the distortion correction unit 5, a current flows accordingly, and a magnetic field in the thickness direction of the movable plate 411a (up and down direction in FIG. 4) is generated. And the direction of the magnetic field is periodically switched. That is, the state A in which the vicinity of the upper side of the coil 415 is the S pole and the vicinity of the lower side is the N pole, and the state B in which the vicinity of the upper side of the coil 415 is the N pole and the vicinity of the lower side is alternately switched.

In the state A, as shown in FIG. 5A, the right side of the permanent magnet 414 is displaced upward by the repulsive force with the magnetic field generated by energizing the coil 415, and the left side of the permanent magnet 414 is the magnetic field. It is displaced downward by the suction force. Thereby, the movable plate 411a is rotated counterclockwise and tilted.
On the contrary, in the state B, as shown in FIG. 5B, the right side of the permanent magnet 414 is displaced downward and the left side of the permanent magnet 414 is displaced upward. Thereby, the movable plate 411a rotates clockwise and tilts.
By alternately repeating the state A and the state B, the movable plate 411a rotates (vibrates) around the rotation center axis J1 while twisting and deforming the connecting portions 411c and 411d.

Further, the current flowing can be adjusted by adjusting the voltage applied from the voltage applying unit 416 to the coil 415 under the control of the distortion correcting unit 5, whereby the movable plate 411 a (the reflecting surface of the light reflecting portion 411 e). The swing angle (amplitude) about the rotation center axis J1 can be adjusted.
The configuration of such an optical scanner 41 is not particularly limited as long as the movable plate 411a can be rotated. For example, the drive system is replaced with electromagnetic drive using a coil 415 and a permanent magnet 414. For example, piezoelectric driving using a piezoelectric element or electrostatic driving using electrostatic attraction may be used.

  As shown in FIG. 3, the optical scanners 41 and 42 having the above-described configuration are provided so that the rotation center axes J1 and J2 are orthogonal to each other. By providing the optical scanners 41 and 42 in this way, the laser light LL emitted from the light source unit 3 can be scanned two-dimensionally (in two directions orthogonal to each other) with respect to the drawing region 91. Thereby, a two-dimensional image can be drawn in the drawing area 91 with a relatively simple configuration.

  More specifically, the light emitted from the light source unit 3 is reflected by the reflecting surface of the light reflecting portion 411e of the light scanner 41, and then reflected by the reflecting surface of the light reflecting portion 421e of the light scanner 42, thereby drawing region. 91 is projected (irradiated). The laser beam LL emitted from the light source unit 3 is rotated by rotating the light reflecting portion 411e of the optical scanner 41 and rotating the light reflecting portion 421e of the optical scanner 42 at an angular velocity slower than the angular velocity (speed). Is scanned in the first direction with respect to the drawing area 91 and in the second direction at a scanning speed slower than the scanning speed in the first direction. Thereby, the laser beam LL emitted from the light source unit 3 is scanned two-dimensionally with respect to the drawing area 91, and an image is drawn in the drawing area 91.

Here, in order to rotate the light reflecting portion 421e of the optical scanner 42 at an angular velocity slower than the angular velocity of the light reflecting portion 411e of the optical scanner 41, for example, the optical scanner 41 is set to resonance driving using resonance, and the optical scanner 42 is used. May be non-resonant drive without using resonance.
The laser beam LL emitted from the light source unit 3 may be first reflected by the light reflecting portion 421e of the light scanner 42 and then reflected by the light reflecting portion 411e of the light scanner 41. That is, it may be configured such that the sub-scanning is performed first and then the main scanning is performed.

Next, the angle detection unit 43 that detects the angle of the movable plate 411a of the optical scanner 41 will be described. Note that the angle detection unit 44 that detects the angle of the movable plate 421a of the optical scanner 42 has the same configuration as the angle detection unit 43, and thus description thereof is omitted.
As shown in FIG. 4, the angle detection means 43 includes a piezoelectric element 431 provided on the connecting portion 411 c of the optical scanner 41, an electromotive force detection unit 432 that detects an electromotive force generated from the piezoelectric element 431, and an electromotive force. And an angle detection unit 433 that obtains an angle of the movable plate 411a based on the detection result of the detection unit 432 (detects the behavior).

  When the connecting portion 411c is torsionally deformed with the rotation of the movable plate 411a, the piezoelectric element 431 is deformed accordingly. When the piezoelectric element 431 is deformed from a natural state to which no external force is applied, the piezoelectric element 431 has a property of generating an electromotive force having a magnitude corresponding to the amount of deformation. Therefore, the angle detection unit 433 includes the electromotive force detection unit 432. Based on the magnitude of the electromotive force detected in step 1, the degree of twist of the connecting portion 411c is obtained, and the angle of the movable plate 411a (the reflection surface of the light reflecting portion 411e) is obtained from the degree of twist. In addition, the angle detection unit 433 obtains a deflection angle around the rotation center axis J1 of the movable plate 411a. A signal including information on the angle and deflection angle of the movable plate 411 a is transmitted from the angle detection unit 433 to the distortion correction unit 5.

The angle of the movable plate 411a to be detected may be set to an angle when any state of the optical scanner 41 is used as a reference (angle is 0 °). For example, the initial state of the optical scanner 41 ( It is possible to set the angle when the reference (angle is 0 °) when the voltage is not applied to the coil 415.
Further, the detection of the angle of the movable plate 411a may be performed in real time (continuously) or may be performed intermittently. Further, the angle detection unit 43 is not limited to the one using the piezoelectric element as in the present embodiment as long as the angle of the movable plate 411a can be detected.

Next, the distortion correction unit 5 will be described.
In the projector 2, when an image is drawn in the drawing area 91 using the pair of optical scanners 41 and 42 as described above, distortion caused by an optical path difference to the drawing area 91, for example, the image is displayed in the drawing area 91. Distortion called “trapezoidal distortion” occurs in which the length in the horizontal direction (first direction) is different between one side and the other side in the second direction of the image. The distortion correction means 5 has a function of correcting such image distortion.

  As shown in FIG. 6, the distortion correction unit 5 includes a video data storage unit (video data storage unit) 51 that stores video data (image data) used when drawing an image, a video data calculation unit 52, A drawing timing generation unit 53, a light source modulation unit (light modulation unit) 54, a deflection angle calculation unit (amplitude calculation unit) 55, an angle instruction unit 56, and a calibration curve storage unit (a calibration curve storage unit) that stores a calibration curve 57).

The projector 2 performs scanning in the first direction (hereinafter also simply referred to as “main scanning”) in each of the forward path and the backward path, and in each of the forward path and the backward path of the sub-scanning, scanning in the second direction (hereinafter, referred to as “main scanning”). An image is drawn in the drawing area 91 by simply performing “sub-scanning” in each of the forward path and the backward path.
Further, the projector 2 performs the first scanning of the laser light LL on the drawing area 91 in a light emitting state in which the laser light LL is emitted from the light source unit 3 (hereinafter also simply referred to as “light emitting state”) during main scanning. Is the deflection angle (hereinafter simply referred to as “the deflection of the movable plate 411a”). The deflection angle of the movable plate 411a is referred to as “the deflection width of the movable plate 411a”. Compared to the case where adjustment (also referred to as “angle”) is not performed (adjustment by the adjustment unit), the deflection angle of the movable plate 411a is adjusted so as to be aligned along the second direction. In particular, it is preferable that the deflection angle of the movable plate 411a is adjusted so that the deflection width of the laser beam LL is constant along the second direction in the light emission state. As a result, it is possible to prevent the trapezoidal distortion of the image while increasing the time aperture ratio. In the present embodiment, a case will be typically described in which the deflection width is adjusted to be constant along the second direction.

  The deflection width is the position of the laser beam LL on the same plane as the drawing area 91 when the movable plate 411a rotates clockwise (predetermined direction) to the maximum angle in the light emission state, and subsequently. The distance (interval) in the first direction between the drawing region 91 and the position of the laser beam LL on the same plane when the movable plate 411a is rotated counterclockwise (in the opposite direction) to the maximum angle, that is, As shown in FIG. 7, when the laser beam LL is two-dimensionally scanned on the drawing area 91 in the light emission state, a plurality of drawing lines (scanning) are traces of the laser light LL on the drawing area 91. Line) L is the length in the first direction.

As shown in FIG. 7, the plurality of drawing lines L are arranged in a zigzag manner. Of each drawing line L, the left end portion and the right end portion each have a small angular velocity (speed) of the light reflecting portion 411e of the optical scanner 41, and are not suitable for drawing. For this reason, a drawing area 91 that is an area for drawing (displaying) an image is set except for the left end and the right end.
When the deflection angle of the movable plate 411a of the optical scanner 41 is constant, the deflection width of the laser beam LL in the light emission state changes according to the angle of the movable plate 421a of the optical scanner 42, and the laser beam LL scans. The position in the second direction (the position of the drawing line L in the second direction) on the drawing area 91 is longer as it is farther from the projector 2. Therefore, in the projector 2, the deflection angle of the movable plate 411a is adjusted according to the angle of the movable plate 421a. That is, as the position in the second direction (the position in the second direction of the drawing line L) on the drawing area 91 scanned with the laser beam LL is farther from the projector 2, the deflection angle of the movable plate 411a is reduced. The fluctuation width of the laser beam LL in the light emission state is made constant along the first direction.

  In the calibration curve storage unit 57, the fluctuation width of the laser beam LL is constant along the second direction in the light emitting state, and the laser beam LL scanned in the drawing region 91 in the second direction on the drawing region 91 is scanned. A calibration curve such as a table or an arithmetic expression (function) indicating the relationship between the position (position of the drawing line L in the second direction) and the deflection angle of the movable plate 411a is stored (stored). When the image is drawn, the calibration curve is used, and the target value (target shake angle) of the shake angle is calculated based on the position of the laser light LL that scans the drawing area 91 in the second direction on the drawing area 91. Ask. The calibration curve can be obtained by calculation and is stored in advance in the calibration curve storage unit 57.

  In the projector 2, in the drawing area 91, for each odd-numbered drawing line L from the upper side, the interval between the adjacent drawing lines L in the second direction is constant. Regarding the drawing lines L, it is preferable to adjust the angle and angular velocity of the movable plate 421a so that the intervals in the second direction between the adjacent drawing lines L are constant. Thereby, distortion in the second direction of the image can be prevented.

  In the present embodiment, for example, the spacing between the adjacent drawing lines L in the second direction is constant at the left end and the right end of the drawing area 91 at the start of drawing of each drawing line L. Thus, the angle of the movable plate 421a is adjusted, and the angular velocity of the movable plate 421a is set to a predetermined value. That is, for each drawing line L, the angle of the movable plate 421a is adjusted so that the interval between the adjacent drawing start points in the second direction is constant, and the angular velocity of the movable plate 421a is a constant value for each drawing line L. Set to. Note that the angular velocity of the movable plate 421a is set to be smaller as the position of the drawing line L in the second direction is farther from the projector 2. Thereby, distortion in the second direction of the image can be prevented with relatively simple control.

Next, the operation of the projector 2 when drawing an image on the drawing area 91 will be described.
First, video data is input to the projector 2. The input video data is temporarily stored in the video data storage unit 51, read from the video data storage unit 51, and an image is drawn using the video data. In this case, drawing of the image may be started after all of the video data is stored in the video data storage unit 51, and after part of the video data is stored in the video data storage unit 51, Drawing may be started, and the video data storage unit 51 may store the video data that follows the drawing of the image.

  When drawing an image after a part of the video data is stored in the video data storage unit 51, first, video data of at least one frame, preferably two frames or more (for example, two frames). Is stored in the video data storage unit 51, and then image drawing is started. This is because the projector 2 draws an image by performing main scanning in each of the forward and backward passes of sub-scanning (hereinafter, also simply referred to as “reciprocating drawing in the second direction”). The drawing order of the video data from the video data storage unit 51 is reversed between when the image is drawn in the scanning forward path and when the image is drawn in the backward scanning backward path. This is because at least one frame of video data used for drawing an image in the return path needs to be stored in the video data storage unit 51 in order to read the video data from the opposite side when starting the video.

The drawing timing generation unit 53 generates drawing timing information and drawing line information, respectively. The drawing timing information is sent to the video data calculation unit 52, and the drawing line information is sent to the deflection angle calculation unit 55.
The drawing timing information includes drawing timing information and the like. The drawing line information includes information on the position (angle of the movable plate 421a) in the second direction of the drawing line L to be drawn. Note that the position of any part of the drawing line L may be set as the position of the drawing line L in the second direction, and examples include the left end, the right end, and the center.

Based on the drawing timing information input from the drawing timing generation unit 53, the video data calculation unit 52 reads the video data corresponding to the pixel to be drawn from the video data storage unit 51, performs various correction calculations, and the like. The luminance data of each color is sent to the light source modulator 54.
The light source modulation unit 54 modulates each light source 320r, 320g, 320b via each drive circuit 310r, 310g, 310b based on the luminance data of each color input from the video data calculation unit 52. That is, the light sources 320r, 320g, and 320b are turned on / off, the output is adjusted (increased / decreased), and the like.

  The angle detection means 43 on the optical scanner 41 side detects the angle and the deflection angle of the movable plate 411a, and draws information on the angle and the deflection angle (angle information of the movable plate 411a) and a drawing timing generation unit 53 and a deflection angle calculation unit. To 55. Further, the angle detector 44 on the optical scanner 42 side detects the angle of the movable plate 421 a and sends information on the angle (angle information of the movable plate 421 a) to the angle instruction unit 56.

When the drawing of the current drawing line L is completed and information on the deflection angle of the movable plate 411a is input from the angle detection unit 43, the drawing timing generation unit 53 synchronizes with the angle indication unit 56 and then Target angle information (angle instruction) indicating the target angle of the movable plate 421a when the laser beam LL is irradiated to the drawing start point of the drawing line L for drawing is sent. The target angle of the movable plate 421a is set so that the interval between the adjacent drawing start points in the second direction is constant. The angle instruction unit 56 compares the angle of the movable plate 421a detected by the angle detection unit 44 with the target angle of the movable plate 421a and performs correction so that the difference becomes zero. Drive data is sent to the drive means 427.
The driving unit 427 drives the optical scanner 42 based on the driving data (applies a voltage to the coil). Thereby, when the laser beam LL is irradiated to the drawing start point, the angle of the movable plate 421a becomes the target angle.

In this embodiment, in each drawing line L, the angular velocity of the movable plate 421a may be constant from the drawing start point to the drawing end point, and the scanning speed of the laser light LL in the second direction may be constant. The angular velocity of the movable plate 421a may be gradually changed, and the scanning speed of the laser light LL in the second direction may be gradually changed.
In addition, the drawing timing generation unit 53 sends drawing line information, that is, information on the position in the second direction of the drawing line L to be drawn next, to the deflection angle calculation unit 55.

  The deflection angle calculation unit 55 uses the calibration curve read from the calibration curve storage unit 57 and is based on the position information in the second direction of the drawing line L to be drawn next input from the drawing timing generation unit 53. Thus, the target deflection angle of the movable plate 411a in the drawing line L to be drawn next is obtained. Then, based on the information on the deflection angle of the movable plate 411a input from the angle detection means 43 and the target deflection angle of the movable plate 411a, the optical scanner is configured so that the deflection angle of the movable plate 411a becomes the target deflection angle. Drive data is sent to 41 drive means 417.

  Based on the driving data, the driving unit 417 applies an effective voltage having the same frequency as the resonance frequency of the optical scanner 41 to the coil 415 to cause a current to flow to generate a predetermined magnetic field. By changing the phase difference between 41 and the drive waveform, energy is supplied to the optical scanner 41, and conversely, energy is taken from the optical scanner 41. As a result, the deflection angle of the movable plate 411a that is in resonance is the target deflection angle. In this way, based on the information (detection result) of the deflection angle of the movable plate 411a detected by the angle detection means 43 and the target deflection angle (target value), the deflection angle of the movable plate 411a is the target deflection angle. The laser beam LL is sequentially scanned on each drawing line L in the drawing area 91 while adjusting the deflection angle of the movable plate 411a so as to draw an image.

  In addition, the drawing timing generation unit 53 manages whether a frame to be drawn is an odd frame (odd number frame) or an even frame (even number frame), so that the movable plate 421a The rotation direction (movement direction) and the reading order of the video data from the video data storage unit 51 are determined. That is, the video data read-out order is reversed between when an image is drawn in an odd frame (scanning path in the second direction) and when an image is drawn in an even frame (scanning return path in the second direction). To.

Further, the laser beam LL is scanned on the same line in the drawing area 91 in the odd frame and the even frame. In other words, the laser beam LL is scanned so that each drawing line L in the odd frame matches each drawing line L in the even frame.
Specifically, for example, as shown in FIG. 7, for the first frame (odd-numbered frame), the drawing starts from the upper left, draws to the lower right zigzag, and the second frame (even-numbered frame) For the frame), the direction of rotation of the movable plate 421a is reversed, and drawing is performed from the lower right to the upper left in the opposite direction. Thereafter, similarly, the odd-numbered frame is drawn from the upper left to the lower right, and the even-numbered frame is drawn from the lower right to the upper left.

In the present embodiment, the forward path of scanning in the second direction is an odd frame and the backward path of scanning in the second direction is an even frame. However, the present invention is not limited to this, and the backward path of scanning in the second direction is an odd number. A frame may be used, and the forward path of scanning in the second direction may be an even frame.
In the present embodiment, the drawing start position for the first frame is at the upper left, but is not limited thereto, and may be, for example, the upper right, the lower left, the lower right, or the like.
Further, the laser beam LL may be scanned on different lines in the drawing area 91 in the odd frame and the even frame.

Here, the change with time of the deflection angle of the movable plate 411a and the change with time of the deflection angle of the movable plate 421a at the time of drawing the image are as follows.
In the main scanning, as shown in FIG. 8, the deflection angle of the movable plate 411a gradually increases from the minimum deflection angle, reaches the maximum deflection angle, gradually decreases, reaches the minimum deflection angle, and then again. The operation is gradually increased, and thereafter the operation is repeated in the same manner. As described above, in the projector 2, the swing angle of the movable plate 411a does not change abruptly. Therefore, the swing angle of the movable plate 411a of the optical scanner 41 configured to operate using resonance can be adjusted easily and reliably. it can.

In the sub-scanning, as shown in FIG. 9, after the swing angle of the movable plate 421a gradually increases from the minimum swing angle, reaches the maximum swing angle, gradually decreases, and then reaches the minimum swing angle. Then, it gradually increases again, and thereafter the operation is repeated in the same manner. As described above, in the projector 2, the swing angle of the movable plate 421 a does not change abruptly. Therefore, the swing angle of the movable plate 421 a of the optical scanner 42 can be adjusted easily and reliably. In addition, a display period (drawing period) in which an image is drawn in an odd-numbered frame (scanning path in the second direction) and a display period in which an image is drawn in an even-numbered frame (scanning return path in the second direction). There is a non-display period (non-drawing period) during which no image is drawn. In this display period, each timing such as a timing for starting drawing of the next frame can be adjusted.
Since the image is drawn both in the forward and backward scans in the second direction, that is, when the movable plate 421a is rotated in a predetermined direction and when the movable plate 421a is rotated in the opposite direction to the above, Such a blanking period becomes unnecessary, and the non-display period can be shortened. Thereby, a time aperture ratio (ratio of the period which draws an image) can be made high.

That is, the non-display period in the second direction in one frame can be shortened by reciprocatingly drawing, thereby increasing the time aperture ratio and drawing an image by performing main scanning only in the sub-scanning forward path. When the angular velocity (velocity) of the movable plate 411a is the same as that when the image is to be performed, the number of frames (frame number) per unit time can be increased as compared with the case where the image is drawn only on the forward path. Thereby, it is possible to easily cope with a fast movement in a moving image. In other words, when the image is drawn by performing the main scan only in the forward path of the sub-scanning and when the number of frames per unit time is the same, the angular velocity of the movable plate 411a is larger than when the image is drawn only in the forward path. Can be made smaller, whereby an image can be stably drawn. In the above case, when the angular velocity of the movable plate 411a is not changed, drawing with higher resolution is possible.
Here, in practice, for example, the inertia (inertia moment) of the movable plates 411a and 421a of the optical scanners 41 and 42 may be large, and the movable plates 411a and 421a may not follow instantaneously. In such a case, for example, the drive current of the optical scanners 41 and 42 may be set to zero, or the optical scanners 41 and 42 may be driven in reverse phase (braking).

As described above, according to the projector 2, it is possible to prevent the trapezoidal distortion of the image by the distortion correcting unit 5 without increasing the deflection angle of the movable plate 411a rapidly while increasing the time aperture ratio. it can.
Further, since the image is drawn by performing the main scan in each of the forward path and the backward path of the sub-scan, the swing angle of the movable plate 421a is suddenly changed when switching from the forward path to the backward path in the sub-scanning or when switching from the backward path to the forward path. Therefore, the deflection angle of the movable plate 421a can be adjusted easily and reliably.

Next, a modified example will be described based on FIG.
In the projector 2 shown in FIG. 10, the fluctuation width of the laser light LL is not constant along the second direction in the light emission state, but the fluctuation width of the laser light LL in the light emission state is that of the movable plate 411a. Compared to the case where the adjustment of the deflection angle is not performed, the deflection angle of the movable plate 411a is adjusted so as to be aligned along the second direction. As a result, the upper width of the drawable area 911 where the image can be drawn is reduced, the shape of the drawable area 911 approaches a rectangle (including a square), and the non-drawn area can be reduced.
In the projector 2, a rectangular drawing area 91 is set in the drawable area 911, and the light source unit 3 is driven so that the laser light LL emitted from the light source unit 3 is projected (irradiated) into the drawing area 91. Control. Thereby, the trapezoid distortion of an image can be prevented.

Next, the human detection unit 6 will be described.
A part of the laser light LL emitted from the light source unit 3 is reflected by the drawing area 91 (floor surface 9) or a person existing in the drawing area 91, and returns to the light scanning section 4 (light reflecting section 411e) again. The returning laser beam LL ′ is obtained. The human detection unit 6 detects the presence or absence of a human being present in the drawing area 91 by using the return laser beam LL ′.

  As shown in FIG. 3, the human detection unit 6 is provided between the light source unit 3 and the optical scanning unit 4, and includes a beam splitter 61 that branches the return laser beam LL ′, and a return laser branched by the beam splitter 61. A photodiode (light receiving element) 62 that receives the light LL ′, a time difference calculation unit 63 connected to the photodiode 62, and a detection unit 64 connected to the time difference calculation unit 63 are included.

The time difference calculation unit 63 includes a timing recording unit 631 connected to the photodiode 62 and a calculation unit 632 connected to the timing recording unit 631.
The timing recording unit 631 is also referred to as a timing at which a predetermined laser beam LL (laser beam LL irradiated to a predetermined position (for example, the central portion) of the drawing area 91) is emitted from the light source unit 3 (hereinafter also referred to as “emission timing”) ) And the timing at which the laser light LL is returned to the laser light LL ′ and received by the photodiode 62 (hereinafter also referred to as “light reception timing”). The timing recording unit 631 records the emission timing and the light reception timing at predetermined time intervals.

  The timing recording unit 631 is connected to the distortion correction unit 5, and a signal transmitted from the distortion correction unit 5 to the light source unit 3 (respective drive circuits 310 r, 310 g, 310 b) and information on the deflection angle of the optical scanners 41, 42. Can be received. The timing recording unit 631 records the emission timing and the light reception timing based on these signals. The timing recording unit 631 may record the two timings based on a signal to the drive circuit 310r, may record the two timings based on a signal to the drive circuit 310b, The two timings may be recorded based on a signal to the drive circuit 310g.

  Each time the predetermined laser beam LL is emitted from the light source unit 3, the calculation unit 632 emits the time difference S between the emission timing and the light reception timing of the laser beam LL (that is, the predetermined laser beam LL is emitted from the light source unit 3. Time from when the light is received by the photodiode 62). The time difference S calculated by the calculation unit 632 is transmitted to the detection unit 64.

  The detection unit 64 stores a time difference S (hereinafter referred to as “reference time difference S1”) when the predetermined laser beam LL is irradiated in a situation where no person is present in the drawing area 91. Then, the detection unit 64 obtains a difference between the time difference S calculated by the time difference calculation unit 63 and the reference time difference S1, and when the difference exceeds a predetermined value, the predetermined laser beam LL on the drawing area 91 is obtained. It is determined that a human is present at the position where the light is irradiated. This is because, in a situation where a human is present at the position where the predetermined laser beam LL is irradiated, the laser beam LL is reflected by the human before the drawing region 91 is irradiated. This is based on the fact that it is shorter than S1.

  Here, although different depending on the size (area), shape, and the like of the drawing area 91, the emission timing and the light reception as described above at a plurality of positions (hereinafter referred to as "time difference calculation positions") of the drawing area 91. It is preferable to calculate the time difference S from the timing (that is, the time from when the laser beam LL is emitted from the light source unit 3 until it is received by the photodiode 62). Further, when there are a plurality of time difference calculation positions, it is preferable that the plurality of time difference calculation positions be set uniformly over the entire drawing area 91. For example, in the case of the drawing area 91 having a rectangular shape as in the present embodiment, it is preferable to set time difference calculation positions at least at the four corners and the center, and it is more preferable to set more time difference calculation positions. As a result, the presence of a person can be detected more accurately in the entire drawing area 91.

  In addition, when a light having a significantly high light reflectance enters the drawing region 91, most of the laser light LL is reflected in a direction other than the light scanning unit 4 by the material having the high reflectance and travels toward the light scanning unit 4. The amount (light quantity) of the return laser beam LL ′ decreases. For this reason, the light receiving output of the return laser beam LL ′ is significantly reduced only in that portion, which may be below the detection limit of the photodiode (light receiving element) 62. Even in that case, it can be recognized that the presence of a person is detected in the drawing area 91. Even with such a determination, it is possible to more accurately detect the presence of a human in the entire drawing area 91.

The human detection by the human detection unit 6 may be performed at any timing. Specifically, it may be performed simultaneously with drawing an image in the drawing area 91. That is, the human detection unit 6 may perform human detection using the laser light LL emitted from the light source unit 3 in order to draw an image in the drawing area 91. The human detection unit 6 may perform human detection when an image is not drawn in the drawing area 91. In this case, for example, the time difference is calculated between the nth frame and the (n + 1) th frame, and the human detection laser beam LL emitted from the light source unit 3 (that is, the laser beam LL that is not used for drawing an image). Irradiate the position. In the latter case, since the laser light LL suitable for human detection can be used, the accuracy of human detection is improved as compared with the former, but it is difficult to perform reciprocal drawing of the image as described above.
According to such a human detection unit 6, it is possible to reliably detect the presence or absence of a human being present in the drawing area 91. In addition, since the main part of the projector 2, that is, the elements necessary for drawing an image can be used effectively, the configuration of the human detection unit 6 can be simplified.

  The configuration of the projector 2 has been described above. By using the optical scanners 41 and 42 for the present embodiment, the configuration of the projector 2 becomes relatively simple. Further, by configuring the projector 2 using the laser beam LL, the function of the human sensor can be easily given to the projector 2. Then, since the projector 2 also serves as a human sensor, the configuration of the image forming apparatus 1 becomes simpler.

The control unit 8 is configured to display images or images drawn in the drawing area 91 when the human detection unit 6 of the projector 2 detects the presence of a person in the drawing area 91 and when a person in the drawing area 91 is not detected. The drive of the projector 2 is controlled so as to change the image pattern.
Specifically, the control unit 8 compares the case where the human detection unit 6 detects the presence of a person in the drawing area 91 with the case where the human detection unit 6 does not detect the presence of a person in the drawing area 91. Thus, the driving of the projector 2 is controlled so that a conspicuous image that is easily recognized by a human in the drawing area 91, that is, attracts attention, is drawn in the drawing area 91. This makes it easy for a person who has entered the drawing area 91 to recognize the image drawn in the drawing area 91. In addition, a person who has entered the drawing area 91 is surprised, interested and interested in an image that has changed due to his / her intrusion, and the phenomenon that the image changes in conjunction with his / her behavior also causes the human to An image drawn in the drawing area 91 can be easily recognized.

Here, the image drawn in the drawing area 91 is not particularly limited, but is preferably an image that can urge (predict) some danger to a person who has entered the drawing area 91.
For example, when the drawing area 91 is formed around a construction area where refurbishment / repair work or the like is being performed, and the human detection unit 6 determines that there is no person in the drawing area 91, FIG. Draw images that prompt danger as shown. Thereby, the person outside the drawing area 91 can recognize the image content. However, not all people outside the drawing area 91 notice the image, and some people who do not notice the image may enter the drawing area 91. As described above, when a human enters the drawing area 91, the image in FIG. 11 is blinked (that is, the image pattern is changed). Thereby, a person who has entered the drawing area 91 can notice the image displayed in the drawing area 91.

  Note that the present invention is not limited to blinking the image, and for example, the brightness of the image may be periodically changed. Further, for example, when a person is not present in the drawing area 91, a still picture is drawn. When a person enters the drawing area 91, the still picture (particularly a character image) is moved in a predetermined direction. You may draw a dynamic video. In addition, when a person enters the drawing area 91, the color and size of the character may be periodically changed, or an image that can further promote danger may be switched. As described above, the same effect as described above can also be achieved by changing the image depending on whether or not there is a person in the drawing area 91.

  When the image forming apparatus 1 is used so as to draw an image that poses a danger to humans in the drawing area 91 as described above, as shown in FIG. It is preferable to scan the laser beam LL on the drawing region 91 from the upper side provided on the side. Usually, a person near the drawing area 91 does not enter the construction area side from the drawing area 91 in order to recognize the image content drawn in the drawing area 91. Therefore, by installing the projector 2 as described above, all the laser beams LL can reach the drawing area 91 without being interrupted by a human or the like, and an image of the studio can be displayed in the drawing area 91. It will be possible to draw. Further, even when a person enters the drawing area 91, the laser light LL that is blocked by the person is applied to a part of the drawing area 91 closer to the construction area than the person (that is, the part located in front of the person). In order to arrive, an image can be drawn in that portion. Therefore, it is possible to make the person recognize the image drawn in the drawing area 91 more reliably.

Second Embodiment
Next, a second embodiment of the image forming apparatus of the present invention will be described.
13 is a schematic plan view showing an optical scanner included in a projector included in an image forming apparatus according to the second embodiment of the invention, FIG. 14 is a cross-sectional view taken along line BB in FIG. 13, and FIG. FIG. 16 is a block diagram showing voltage applying means of driving means included in the optical scanner shown in FIG. 13, and FIG. 16 is a diagram showing an example of voltages generated in the first voltage generating section and the second voltage generating section shown in FIG. 17A and 17B are diagrams (a is a side view, and b is a front view) for explaining the operation of the projector provided in the image forming apparatus according to the second embodiment of the present invention. In the following, for convenience of explanation, the front side of the page in FIG. 13 is called “up”, the back side of the page is called “down”, the right side is called “right”, the left side is called “left”, and the upper side in FIG. The upper side, the lower side is called “lower”, the right side is called “right”, and the left side is called “left”.

Hereinafter, the image forming apparatus according to the second embodiment will be described with a focus on differences from the first embodiment described above, and description of similar matters will be omitted.
The image forming apparatus of the second embodiment is different from that of the first embodiment except that the configuration of the optical scanner provided in the projector is different and the trajectory of scanning (main scanning) in the first direction on the drawing area is not a straight line. It is almost the same. In FIG. 15 and FIG. 17, the same reference numerals are given to the same configurations as those in the above-described embodiment.

The optical scanning unit 4 has one optical scanner 45 of a so-called two-degree-of-freedom vibration system.
The optical scanner 45 includes a base 46 provided with a first vibration system 46a, a second vibration system 46b, and a support portion 46c as shown in FIG. 13, a counter substrate 47 disposed to face the base 46, and the base 46. A spacer member 48 provided between the counter substrate 47, a permanent magnet 491, and a coil 492 are provided.

The first vibration system 46a includes a frame-shaped drive unit 461a provided inside the frame-shaped support unit 46c, and a pair of first connection units 462a that support the drive unit 461a on the support unit 46c. 463a.
The second vibration system 46b includes a movable plate 461b provided inside the drive unit 461a, and a pair of second coupling portions 462b and 463b that support the movable plate 461b on both sides of the drive unit 461a. Yes.

The drive unit 461a has an annular shape in a plan view of FIG. The shape of the drive unit 461a is not particularly limited as long as it has a frame shape. For example, the drive unit 461a may have a quadrangular ring shape in a plan view of FIG. A permanent magnet 491 is joined to the lower surface of the driving unit 461a.
Each of the first connecting portions 462a and 463a has a longitudinal shape and can be elastically deformed. The first connecting portions 462a and 463a connect the driving portion 461a and the supporting portion 46c so that the driving portion 461a can be rotated with respect to the supporting portion 46c. The first connecting portions 462a and 463a are provided coaxially with each other, and the drive portion 461a is located with respect to the support portion 46c around this axis (hereinafter referred to as “rotation center axis J3”). And is configured to rotate.
The first connecting portion 462a is provided with a piezoelectric element 465a for detecting the angle (the turning angle around the turning central axis J3) (behavior) of the driving portion 461a.

  The movable plate 461b has a circular shape in plan view of FIG. The shape of the movable plate 461b is not particularly limited as long as the movable plate 461b can be formed inside the drive unit 461a. For example, the shape of the movable plate 461b may be an ellipse or a quadrangle in a plan view of FIG. May be. A light reflecting portion 464b having light reflectivity is formed on the upper surface of the movable plate 461b.

Each of the second connecting portions 462b and 463b has a longitudinal shape and can be elastically deformed. The second connecting portions 462b and 463b connect the movable plate 461b and the driving portion 461a so that the movable plate 461b can be rotated with respect to the driving portion 461a, respectively. Such second connecting portions 462b and 463b are provided coaxially with each other, and the movable plate 461b is located with respect to the drive portion 461a around this axis (hereinafter referred to as “rotation center axis J4”). It is configured to rotate.
The second connecting portion 462b is provided with a piezoelectric element 465b for detecting the angle (rotation angle around the rotation center axis J4) (behavior) of the movable plate 461b.

As shown in FIG. 13, the rotation center axis J3 and the rotation center axis J4 are orthogonal to each other. Further, the centers of the drive unit 461a and the movable plate 461b are respectively located on the intersections of the rotation center axis J3 and the rotation center axis J4 in the plan view of FIG. Hereinafter, for convenience of explanation, an intersection of the rotation center axis J3 and the rotation center axis J4 is also referred to as an “intersection point G”.
As shown in FIG. 14, the base body 46 as described above is bonded to the counter substrate 47 via the spacer member 48. A coil 492 that generates a magnetic field acting on the permanent magnet 491 is provided on the upper surface of the counter substrate 47.

  The permanent magnet 491 passes through the intersection point G in the plan view of FIG. 13 and is inclined with respect to the rotation center axis J3 and the rotation center axis J4 (this line segment is referred to as “line segment M”). (Also called). Such a permanent magnet 491 has an S pole on one side in the longitudinal direction with respect to the intersection point G and an N pole on the other side. In FIG. 14, the left side of the permanent magnet 491 in the longitudinal direction is the S pole and the right side is the N pole.

  In the plan view of FIG. 13, the inclination angle θ of the line segment M with respect to the rotation center axis J3 is preferably 30 to 60 degrees, more preferably 40 to 50 degrees, and approximately 45 degrees. Is more preferable. By providing the permanent magnet 491 in this manner, the movable plate 461b can be smoothly rotated around the rotation center axis J3 and the rotation center axis J4. In the present embodiment, the line segment M is inclined about 45 degrees with respect to the rotation center axis J3 and the rotation center axis J4.

  Further, as shown in FIG. 14, a concave portion 491 a is formed on the upper surface of the permanent magnet 491. The recess 491a is an escape portion for preventing contact between the permanent magnet 491 and the movable plate 461b. By forming such a recess 491a, it is possible to prevent the movable plate 461b from coming into contact with the permanent magnet 491 when the movable plate 461b rotates around the rotation center axis J3.

The coil 492 is formed so as to surround the outer periphery of the drive unit 461a in the plan view of FIG. Thereby, when the optical scanner 45 is driven, contact between the drive unit 461a and the coil 492 can be reliably prevented. As a result, the distance between the coil 492 and the permanent magnet 491 can be made relatively short, and the magnetic field generated from the coil 492 can be efficiently applied to the permanent magnet 491.
The coil 492 is electrically connected to the voltage application unit 493, and when a voltage is applied to the coil 492 by the voltage application unit 493, the respective axes of the rotation center axis J3 and the rotation center axis J4 from the coil 492. A magnetic field is generated in the axial direction perpendicular to.

  As shown in FIG. 15, the voltage applying means 493 includes a first voltage generator 493a that generates a first voltage V1 for rotating the movable plate 461b about the rotation center axis J3, and a movable plate 461b. A second voltage generator 493b that generates a second voltage V2 for rotating around the rotation center axis J4 is superimposed on the first voltage V1 and the second voltage V2, and the voltage is applied to the coil 492. And a voltage superimposing portion 493c to be applied.

Similarly to FIG. 9 of the first embodiment, the first voltage generator 493a generates the first voltage V1 that periodically changes at a period T1 that is twice the frame frequency, as shown in FIG. 16A. Is.
The first voltage V1 has a waveform like a triangular wave. Therefore, the optical scanner 45 can effectively reciprocate (sub-scan) light. Note that the waveform of the first voltage V1 is not limited to this. Here, the frequency (1 / T1) of the first voltage V1 is not particularly limited as long as it is a frequency suitable for sub-scanning, but is preferably 15 to 40 Hz (about 30 Hz).

In the present embodiment, the frequency of the first voltage V1 is different from the torsional resonance frequency of the first vibration system 46a configured by the drive unit 461a and the pair of first coupling units 462a and 463a. Has been adjusted.
On the other hand, as shown in FIG. 16B, the second voltage generator 493b generates a second voltage V2 that periodically changes at a period T2 different from the period T1.

The second voltage V2 has a waveform like a sine wave. Therefore, the optical scanner 45 can perform main scanning of light effectively. Note that the waveform of the second voltage V2 is not limited to this.
The frequency of the second voltage V2 is not particularly limited as long as it is higher than the frequency of the first voltage V1 and suitable for main scanning, but is preferably 10 to 40 kHz. As described above, the frequency of the second voltage V2 is set to 10 to 40 kHz, and the frequency of the first voltage V1 is set to about 30 Hz as described above, so that the movable plate 461b can be moved at a frequency suitable for drawing on the screen. It can be rotated around the rotation center axis J3 and the rotation center axis J4. However, if the movable plate 461b can be rotated around each of the rotation center axis J3 and the rotation center axis J4, the combination of the frequency of the first voltage V1 and the frequency of the second voltage V2 can be obtained. There is no particular limitation.

In the present embodiment, the frequency of the second voltage V2 is adjusted to be equal to the torsional resonance frequency of the second vibration system 46b configured by the movable plate 461b and the pair of second connecting portions 462b and 463b. Has been. Thereby, the rotation angle of the movable plate 461b around the rotation center axis J3 can be increased.
When the resonance frequency of the first vibration system 46a is f ₁ [Hz] and the resonance frequency of the second vibration system 46b is f ₂ [Hz], f ₁ and f ₂ are f ₂ > f. ₁ is preferably satisfied, and more preferably f ₂ ≧ 10f ₁ is satisfied. As a result, the movable plate 461b is rotated more smoothly around the rotation center axis J3 at the frequency of the first voltage V1, and more smoothly at the frequency of the second voltage V2 around the rotation center axis J4. Can do.

The first voltage generation unit 493a and the second voltage generation unit 493b are each connected to the distortion correction unit 5 and driven based on a signal from the distortion correction unit 5. The voltage superimposing unit 493c is connected to the first voltage generating unit 493a and the second voltage generating unit 493b.
The voltage superimposing unit 493c includes an adder 493d for applying a voltage to the coil 492. The adder 493d receives the first voltage V1 from the first voltage generator 493a and receives the second voltage V2 from the second voltage generator 493b, and superimposes these voltages and applies them to the coil 492. It has become.

The optical scanner 45 configured as described above is driven as follows.
For example, the first voltage V1 as shown in FIG. 16A and the second voltage V2 as shown in FIG. 16B are superimposed by the voltage superimposing unit 493c, and the superimposed voltage is applied to the coil 492. Applied (this superimposed voltage is also referred to as “voltage V3”).
Then, with the voltage corresponding to the first voltage V1 in the voltage V3, the magnetic pole that tries to attract the south pole side of the permanent magnet 491 to the coil 492 and the N pole side away from the coil 492, and the permanent The magnetic poles of the magnet 491 that try to move the S pole side away from the coil 492 and that try to attract the N pole side to the coil 492 are alternately switched. Thereby, the drive part 461a rotates around the rotation center axis J3 at the frequency of the first voltage V1 together with the movable plate 461b while twisting and deforming the first coupling parts 462a and 463a.

  The frequency of the first voltage V1 is set to be extremely lower than the frequency of the second voltage V2, and the resonance frequency of the first vibration system 46a is the resonance frequency of the second vibration system 46b. Designed lower than. Therefore, the first vibration system 46a is easier to vibrate than the second vibration system 46b, and the first voltage V1 causes the movable plate 461b to rotate around the rotation center axis J4. Can be prevented.

On the other hand, a magnetic field that attempts to attract the south pole side of the permanent magnet 491 to the coil 492 and to separate the north pole side from the coil 492 with a voltage corresponding to the second voltage V2 in the voltage V3, and a permanent The magnetic poles of the magnet 491 that try to move the S pole side away from the coil 492 and that try to attract the N pole side to the coil 492 are alternately switched. As a result, the movable plate 461b rotates around the rotation center axis J4 at the frequency of the second voltage V2 while twisting and deforming the second connecting portions 462b and 463b.
Since the frequency of the second voltage V2 is equal to the torsional resonance frequency of the second vibration system 46b, the movable plate 461b is predominantly rotated around the rotation center axis J4 by the second voltage V2. Can do. Therefore, it is possible to prevent the movable plate 461b from rotating around the rotation center axis J3 together with the drive unit 461a by the second voltage V2.

  According to the optical scanner 45 as described above, laser light (light) can be scanned two-dimensionally with one actuator, and space saving of the optical scanning unit 4 can be achieved. For example, when a pair of optical scanners are used as in the first embodiment, the relative positional relationship between these optical scanners must be set with high accuracy, but this is not necessary in this embodiment. The manufacturing can be facilitated.

Further, in the present embodiment, unlike FIG. 7 of the first embodiment, as shown in FIG. 17, the laser light LL is emitted on the drawing area 91 in the light emission state in which the laser light (light) LL is emitted from the light source unit 3. A plurality of drawing lines L that are the locus of the laser beam LL on the drawing area 91 when two-dimensionally scanned are arranged in a zigzag manner and distorted.
Further, since the scanning line L is distorted, the video data calculation unit 52 reads out from the video data storage unit 51 while calculating data corresponding to pixel data to be drawn on the line to be scanned, and draws a drawing timing. After performing various correction calculations based on the drawing timing information input from 53, the luminance data of each color is sent to the light source modulator 54.
Regarding processing other than the above, the same processing as in the first embodiment is performed.
Also by such 2nd Embodiment, the effect similar to 1st Embodiment can be exhibited.

  The image forming apparatus of the present invention has been described based on the illustrated embodiment. However, the present invention is not limited to this, and the configuration of each unit is replaced with an arbitrary configuration having the same function. can do. In addition, any other component may be added to the present invention. Further, the present invention may be a combination of any two or more configurations (features) of the above embodiments.

In the first embodiment, a pair of optical scanners is used as the optical scanning unit. However, the present invention is not limited to this. For example, an optical scanner and a galvanometer mirror may be used. In this case, it is preferable to use a galvanometer mirror for sub scanning.
In the above embodiment, the three dichroic mirrors are used to combine the red laser light, the green laser light, and the blue laser light to emit one laser light (light). However, the dichroic prism or the like is used. May be combined.

  In the above-described embodiment, the light source unit has a configuration including a laser light source that emits a red laser, a laser light source that emits a blue laser, and a laser light source that emits a green laser. For example, a laser light source that emits a red laser, a laser light source that emits a blue laser, and a laser light source that emits an ultraviolet laser may be provided. In this case, the drawing region includes a phosphor that generates green fluorescence when irradiated with an ultraviolet laser. Thereby, a full-color image can be displayed in the drawing area.

  In the above-described embodiment, the configuration using the human detection unit incorporated in the projector as the human sensor has been described. However, the present invention is not limited to this, for example, an infrared sensor or a sensor provided separately from the projector. An ultrasonic sensor may be used. In this case, it is better to make the effective detection area of the sensor substantially coincide with the drawing area. Thus, if the sensor detects a person, it means that a person is present in the drawing area. Therefore, it is possible to easily detect the presence or absence of a person existing in the drawing area. Further, for example, one or a plurality of first pressure sensors installed under the floor of the drawing area may be used as the human sensor. In this case, if the pressure sensor reacts, it can be determined that a person is present in the drawing area.

  DESCRIPTION OF SYMBOLS 1 ... Image forming apparatus 2 ... Projector 3 ... Light source unit 31r, 31g, 31b ... Laser light source 310r, 310g, 310b ... Drive circuit 320r, 320g, 320b ... Light source 32r, 32g, 32b ... Collimator Lenses 33r, 33g, 33b ... Dichroic mirror 4 ... Optical scanning part 41 ... Optical scanner 411 ... Base 411a ... Movable plate 411b ... Supporting part 411c, 411d ... Connecting part 411e ... Light reflecting part 412 ... ... spacer member 413 ... counter substrate 414 ... permanent magnet 415 ... coil 416 ... voltage application means 417 ... drive means 42 ... optical scanner 421a ... movable plate 421e ... light reflecting portion 427 ... drive means 43 ... Angle detection means 431 ... Piezoelectric element 432 ... Electromotive force detection unit 433 …… Angle detection unit 44 …… Angle detection means 45 …… Optical scanner 46 …… Substrate 46a …… First vibration system 46b …… Second vibration system 46c …… Supporting unit 461a …… Drive Part 461b... Movable plate 462a, 463a... First connecting part 462b, 463b... Second connecting part 464b .. Light reflecting part 465a, 465b .. Piezoelectric element 47 .. Counter substrate 48. ...... Permanent magnet 491a ...... Recess 492 ... Coil 493 ... Voltage application means 493a ... First voltage generator 493b ... Second voltage generator 493c ... Voltage superposition unit 493d ... Adder 5 ... Distortion correction means 51 …… Video data storage unit 52 …… Video data calculation unit 53 …… Drawing timing generation unit 54 …… Light source modulation unit 55 …… Vibration Angle calculation unit 56 …… Angle instruction unit 57 …… Calibration curve storage unit 6 …… Human detection unit 61 …… Beam splitter 62 …… Photo diode 63 …… Time difference calculation unit 631 …… Timing storage unit 632 …… Calculation unit 64 …… Detector 8 …… Control means 9 …… Floor surface 91 …… Drawing area 911 …… Drawable area G …… Intersection J1, J2, J3, J4 …… Rotation center axis L …… Drawing line LL …… Laser light M …… Line segment

Claims (10)

A projector configured to draw an image by scanning a light beam in a drawing area formed on a display surface;
A human sensor for detecting whether a human is present in the drawing area;
Control means for controlling driving of the projector so as to change an image or an image pattern drawn in the drawing area depending on whether the human sensor detects the presence of a person in the drawing area or not. An image forming apparatus comprising:   When the human sensor detects the presence of a person in the drawing area, the control means detects the human being compared to a case where the human sensor does not detect the presence of a person in the drawing area. The image forming apparatus according to claim 1, wherein the driving of the projector is controlled so that an easily recognized image is drawn in the drawing area.   When the human sensor detects the presence of a person in the drawing area, the control means draws an image that can urge a person in the drawing area to pose a danger. The image forming apparatus according to claim 1, wherein the driving of the projector is controlled. The projector includes a light emitting unit that emits a laser;
A movable plate provided with a light reflecting portion for reflecting the laser emitted from the light emitting portion is provided so as to be rotatable in at least one direction or two directions orthogonal to each other, and the laser reflected by the light reflecting portion by the rotation The image forming apparatus according to claim 1, further comprising: an optical scanner that scans the display surface.   The image forming apparatus according to claim 4, wherein the projector also serves as the human sensor.   The said human sensor detects the person who exists in the said drawing area based on the said laser beam radiate | emitted from the said light emission part and reflected by the person who exists in the said drawing area. Image forming apparatus.   The human sensor is provided in the middle of the optical path between the light emitting unit and the light reflecting unit or at a branched position, and reflects the light reflected by the drawing region or the human and returned to the light reflecting unit again. Based on a light receiving unit that receives light, a time difference calculating unit that calculates a time difference between a timing at which light is emitted from the light emitting unit and a timing at which the light is received by the light receiving unit, and a calculation result by the time difference calculating unit The image forming apparatus according to claim 6, further comprising: a detection unit that detects the presence of a person in the drawing area.   The human sensor is provided in the middle of the optical path between the light emitting unit and the light reflecting unit or at a branched position, and receives light reflected from the drawing area and returned to the light reflecting unit again. The image forming apparatus according to claim 6, further comprising: a detection unit that detects the presence of a person in the drawing area based on the light intensity detected by the unit.   The image forming apparatus according to claim 1, wherein the projector includes a distortion correction unit that corrects distortion of an image displayed on the display surface.   The image forming apparatus according to claim 1, wherein the display surface is a floor surface.

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