JP2013218007A - Support device, method for controlling the same and projection system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a support device, a method for controlling the same and a projection system capable of correcting trapezoidal distortion with a simple structure without deteriorating an image.SOLUTION: When a second gear 35 is rotated by drive of a right and left drive motor 26, the second gear 35 rotates (revolves) around a first gear 34. In fact, a housing 6 and a projector 1 fixed thereto rotate in a horizontal direction, a direction where a projected image on a projection surface moves from side to side, with a main axis 33 parallel to a vertical direction as a rotation axis. A support device 5 measures reception intensity of ultrasonic waves reflected from a projection surface while changing positions (inclinations) of the projector 1 and adjusts the position on the basis of a measurement result so that a light axis Ax of a projection lens 13 becomes orthogonal to the projection surface. The receiving intensity peaks when the light axis Ax is orthogonal to the projection surface and decreases as the inclination of the light axis Ax to the projection surface deviates from a right angle.

Description

  The present invention relates to a support device that supports a projector that projects image light, a control method thereof, and a projection system.

  When a projector that projects image light is installed with an inclination with respect to a projection surface such as a screen, a trapezoidal distortion occurs in which a displayed image is deformed into a trapezoid. For this reason, various techniques for automatically correcting trapezoidal distortion according to the installation state of the projector have been proposed (see, for example, Patent Document 1). In Patent Document 1, an angle of inclination with a screen is detected by observing the level of a reflected wave while rotating a distance sensor that irradiates ultrasonic waves or light, and is detected for an input video signal. A projection display device that corrects trapezoidal distortion by performing image processing (digital processing) according to an inclination angle has been proposed.

JP 2004-134908 A

  However, the aspect of correcting the trapezoidal distortion by image processing has a problem that the image deteriorates because the keystone distortion is canceled by previously distorting the image in the opposite direction. In particular, when an image including fine dots and lines regularly arranged is displayed, a wavy striped pattern (interference fringe) called moire is generated and display quality is remarkably deteriorated. Further, since the projector remains inclined with respect to the projection plane, there is a large difference in projection distance depending on the position in the image, and it is difficult to achieve an appropriate focus state over the entire area of the image.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

  Application Example 1 A support device according to this application example transmits a predetermined transmission wave to the projection unit, a support unit that supports a projector that projects image light based on image information from the projection optical system onto the projection surface, and the projection surface. A transmission / reception unit that receives the transmission wave reflected by the projection surface, a drive unit that rotates the projector integrally with the transmission / reception unit, and the transmission wave to the transmission / reception unit while rotating the projector by the drive unit. And an adjustment unit that adjusts the angle of the projector by the drive unit so that the optical axis of the projection optical system is perpendicular to the projection plane based on the result of the transmission / reception. It is characterized by.

  According to this support apparatus, the adjustment unit causes the transmission / reception unit to transmit / receive transmission waves while rotating the projector integrally with the transmission / reception unit, and based on the result of the transmission / reception, the optical axis of the projection optical system is changed to the projection surface. Adjust the projector angle so that it is vertical. In this way, since the projector is rotated so that the optical axis of the projection optical system is perpendicular to the projection plane, it becomes possible to correct trapezoidal distortion without image processing, and to suppress image degradation due to image processing. It becomes possible to do.

  Application Example 2 In the support device according to the application example described above, the support device according to the application example further includes a projection surface switching unit that rotates the projector by the driving unit to switch the projection surface, and the adjustment unit includes the projection surface switching unit You may make it adjust the angle of the said projector after switching a projection surface.

  According to this support apparatus, since the adjustment unit adjusts the angle of the projector after the projection plane switching unit switches the projection plane, it is possible to easily correct the trapezoidal distortion that may occur when the projection plane is switched. Become.

  Application Example 3 In the support device according to the application example described above, the adjustment unit may adjust the angle of the projector based on a change in reception intensity of the transmission wave.

  Application Example 4 In the support device according to the application example, the transmission / reception unit transmits the transmission wave toward the projection plane in parallel with the optical axis of the projection optical system, and the adjustment unit is the projector May be adjusted to an angle at which the reception intensity becomes maximum.

  Application Example 5 In the support device according to the application example, the transmission / reception unit transmits the transmission wave toward the projection plane in parallel with the optical axis of the projection optical system, and the adjustment unit is the projector Is preferably adjusted to an intermediate angle between two angles at which the received intensity is a predetermined value smaller than the maximum value.

  According to this support apparatus, the adjustment unit adjusts the angle of the projector to an intermediate angle between two angles at which the reception intensity is a predetermined value smaller than the maximum value. Here, the angle at which the reception strength is a predetermined value smaller than the maximum value has a larger amount of change in the reception strength with respect to the change in angle than the angle at which the reception strength is maximum. It is hard to receive. For this reason, the optical axis of the projection optical system is more accurately perpendicular to the projection plane by adjusting the angle of the projector to an intermediate angle between two angles at which the received intensity is smaller than the maximum value. can do.

  Application Example 6 In the support device according to the application example described above, the transmission / reception unit is on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the driving unit. May be located.

  Application Example 7 In the support device according to the application example, the adjustment unit may adjust the angle of the projector based on a change in arrival time of the transmission wave.

  Application Example 8 In the support device according to the application example described above, the transmission / reception unit is on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the driving unit. The adjusting unit may adjust the angle of the projector to an angle that minimizes the arrival time.

  Application Example 9 In the support device according to the application example described above, the transmission / reception unit is on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the driving unit. The adjustment unit adjusts the angle of the projector to an intermediate angle between the two angles at which the arrival time is a predetermined value larger than the minimum value. It is desirable.

  According to this support apparatus, the adjustment unit adjusts the angle of the projector to an intermediate angle between the two angles at which the arrival time is a predetermined value greater than the minimum value. Here, the angle at which the arrival time is a predetermined value greater than the minimum value is larger in the amount of change in the distance to the projection surface with respect to the change in angle, that is, the amount of change in the arrival time, than the angle at which the arrival time is minimum. , Less susceptible to errors when measuring arrival time. For this reason, the optical axis of the projection optical system is more accurately perpendicular to the projection plane by adjusting the angle of the projector to an intermediate angle between two angles that are larger than the minimum value of the arrival time. can do.

  Application Example 10 A projection system according to this application example includes the support device according to the application example and the projector.

  According to this projection system, the same effect as that of the support device can be obtained.

  Application Example 11 A support device control method according to this application example includes a support unit that supports a projector that projects image light based on image information from a projection optical system onto a projection surface, and a predetermined transmission wave on the projection surface. A control method for a support device, comprising: a transmission / reception unit that transmits and receives the transmission wave reflected by the projection plane; and a drive unit that rotates the projector integrally with the transmission / reception unit. The transmission unit transmits and receives the transmission wave while rotating the projector by the unit, and based on the result of the transmission and reception, the drive unit causes the optical axis of the projection optical system to be perpendicular to the projection plane. An adjustment step of adjusting the angle of the projector.

  According to the control method of the support device, in the adjustment step, the transmission / reception unit transmits / receives the transmission wave while rotating the projector integrally with the transmission / reception unit, and the optical axis of the projection optical system is determined based on the transmission / reception result. Adjust the projector angle so that it is perpendicular to the projection plane. In this way, since the projector is rotated so that the optical axis of the projection optical system is perpendicular to the projection plane, it becomes possible to correct trapezoidal distortion without image processing, and to suppress image degradation due to image processing. It becomes possible to do.

  Application Example 12 In the method for controlling a support device according to the application example, the projector further includes a projection plane switching step of rotating the projector to switch the projection plane, and the adjustment step includes the projection plane switching. The angle of the projector may be adjusted after switching the projection plane in the step.

  According to the control method of the support device, in the adjustment step, the angle of the projector is adjusted after the projection plane is switched in the projection plane switching step. Therefore, the trapezoidal distortion that can be caused by the switching of the projection plane can be easily corrected. Is possible.

  Application Example 13 In the support device control method according to the application example described above, in the adjustment step, the angle of the projector may be adjusted based on a change in reception intensity of the transmission wave.

  Application Example 14 In the control method of the support device according to the application example, the transmission / reception unit transmits the transmission wave toward the projection plane in parallel with the optical axis of the projection optical system. The angle of the projector may be adjusted to an angle that maximizes the reception intensity.

  Application Example 15 In the method for controlling a support device according to the application example, the transmission / reception unit transmits the transmission wave toward the projection plane in parallel with the optical axis of the projection optical system. It is desirable to adjust the angle of the projector to an intermediate angle between two angles at which the reception intensity is a predetermined value smaller than the maximum value.

  According to the control method of the support device, in the adjustment step, the angle of the projector is adjusted to an intermediate angle between two angles at which the reception intensity is a predetermined value smaller than the maximum value. Here, the angle at which the reception strength is a predetermined value smaller than the maximum value has a larger amount of change in the reception strength with respect to the change in angle than the angle at which the reception strength is maximum. It is hard to receive. For this reason, the optical axis of the projection optical system is more accurately perpendicular to the projection plane by adjusting the angle of the projector to an intermediate angle between two angles at which the received intensity is smaller than the maximum value. can do.

  Application Example 16 In the method of controlling the support device according to the application example, the transmission / reception unit passes through the rotation axis and is parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the driving unit. It may be located on a straight line.

  Application Example 17 In the support device control method according to the application example described above, in the adjustment step, the angle of the projector may be adjusted based on a change in arrival time of the transmission wave.

  Application Example 18 In the control method of the support device according to the application example, the transmission / reception unit passes through the rotation axis and is parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the driving unit. It may be positioned on the projection plane side with respect to the rotation axis on a straight line, and in the adjustment step, the angle of the projector may be adjusted to an angle that minimizes the arrival time.

  Application Example 19 In the method of controlling a support device according to the application example, the transmission / reception unit passes through the rotation axis and is parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the driving unit. It is located on the projection plane side with respect to the rotation axis on a straight line, and in the adjustment step, the angle of the projector is an intermediate angle between two angles at which the arrival time is a predetermined value greater than the minimum value It is desirable to adjust to.

  According to the control method of the support device, in the adjustment step, the angle of the projector is adjusted to an intermediate angle between the two angles at which the arrival time is a predetermined value larger than the minimum value. Here, the angle at which the arrival time is a predetermined value greater than the minimum value is larger in the amount of change in the distance to the projection surface with respect to the change in angle, that is, the amount of change in the arrival time, than the angle at which the arrival time is minimum. , Less susceptible to errors when measuring arrival time. For this reason, the optical axis of the projection optical system is more accurately perpendicular to the projection plane by adjusting the angle of the projector to an intermediate angle between two angles that are larger than the minimum value of the arrival time. can do.

  Further, in the case where the above-described support device and its control method are constructed using a computer, the above-described form and the application example are such that the program for realizing the function or the program can be read by the computer. It can also be configured in the form of a recorded recording medium or the like. Recording media include flexible disks, hard disks, optical disks such as CDs and DVDs, magneto-optical disks, memory cards and USB memories equipped with non-volatile semiconductor memory, and internal storage devices for support devices (semiconductor memories such as RAM and ROM). For example, various media that can be read by the computer can be used.

It is a figure which shows the room provided with the projection system of 1st Embodiment, (a) is a side view, (b) is a top view. 1 is a block diagram showing a schematic configuration of a projector. The block diagram which shows schematic structure of the support apparatus of 1st Embodiment. It is a schematic diagram for demonstrating the attitude | position adjustment mechanism of the support apparatus of 1st Embodiment, (a) is a side view, (b) is a top view. The flowchart for demonstrating operation | movement of the support apparatus at the time of switching a projection surface. The flowchart for demonstrating the trapezoid distortion correction process of 1st Embodiment. The flowchart for demonstrating the trapezoid distortion correction process of 2nd Embodiment. The figure which shows the directivity of the ultrasonic transmission / reception part which attached the horn. The flowchart for demonstrating the trapezoid distortion correction process of 3rd Embodiment. The flowchart for demonstrating the trapezoid distortion correction process of 4th Embodiment. The flowchart for demonstrating the trapezoid distortion correction process of 5th Embodiment. The flowchart for demonstrating the trapezoid distortion correction process of 6th Embodiment. The flowchart for demonstrating the trapezoid distortion correction process of 7th Embodiment. The flowchart for demonstrating the trapezoid distortion correction process of 8th Embodiment.

(First embodiment)
Hereinafter, the projection system of the first embodiment will be described with reference to the drawings.
FIG. 1 is a view showing a room provided with the projection system of the present embodiment, in which (a) is a side view and (b) is a plan view.
As shown in FIGS. 1A and 1B, the projection system 100 includes a projector 1 and a support device 5. The projector 1 includes a housing 2 constituting an exterior, and a projection lens 13 that projects image light is exposed on the front surface 2 f of the housing 2. The projector 1 is a ceiling-suspended projector, for example, is attached to a ceiling C of a room R surrounded by walls on all sides by a support device 5 and receives image light from a projection lens 13 on a wall surface (projection surface S). Project.

  The support device 5 is a device for supporting the projector 1 and includes a housing 6 constituting an exterior. The support device 5 can rotate the projector 1 horizontally with respect to the ceiling C in a state where the projector 1 is supported. By rotating the projector 1 in units of 90 °, four wall surfaces (projections) An image can be projected onto any one of the surfaces S).

  Here, when the optical axis Ax of the projection lens 13 of the projector 1 and the projection surface S to be projected are perpendicular, the image projected from the projector 1 has an original shape (rectangular shape) on the projection surface S. Is displayed. On the other hand, when the projector 1 is inclined with respect to the projection surface S to be projected and the optical axis Ax of the projection lens 13 is not perpendicular to the projection surface S, the projected image is distorted into a trapezoidal shape. Therefore, the projection system 100 according to the present embodiment can correct the trapezoidal distortion (trapezoid distortion) by adjusting the attitude of the projector 1, that is, the horizontal inclination (rotation angle) of the projector 1. (Details will be described later). Note that the direction from the projector 1 toward the projection surface S to be projected is the forward direction, the opposite direction is the rear direction, the direction toward the left side when viewed from the front direction is the left direction, the direction toward the right side is the right direction, and the vertical direction Of these, the direction against gravity is the upward direction, and the direction of gravity is the downward direction.

FIG. 2 is a block diagram illustrating a schematic configuration of the projector 1.
As shown in FIG. 2, the projector 1 includes an image projection unit 10, an image information input unit 15, an image processing unit 16, a liquid crystal drive unit 17, and the like, which are accommodated in a housing 2 (see FIG. 1). Has been.

  The image projection unit 10 includes a light source device 11 as a light source, three liquid crystal light valves 12R, 12G, and 12B as light modulation devices, a projection lens 13 as a projection optical system, and the like. The image projection unit 10 corresponds to a display unit. The image projection unit 10 modulates light emitted from the light source device 11 into image light using the liquid crystal light valves 12R, 12G, and 12B, and projects the image light from the projection lens 13. The image is displayed on the projection surface S.

  The light source device 11 includes a discharge-type light source lamp 11a made of an ultra-high pressure mercury lamp, a metal halide lamp, or the like, and a reflector 11b that reflects light emitted from the light source lamp 11a toward the liquid crystal light valves 12R, 12G, and 12B. Has been. The light emitted from the light source device 11 is converted into light having a substantially uniform luminance distribution by an integrator optical system (not shown), and red (R), green (G), which are the three primary colors of light by a color separation optical system (not shown), After being separated into blue (B) color light components, they are incident on the liquid crystal light valves 12R, 12G, and 12B, respectively.

  The liquid crystal light valves 12R, 12G, and 12B are configured by a liquid crystal panel in which liquid crystal is sealed between a pair of transparent substrates. The liquid crystal light valves 12R, 12G, and 12B include a rectangular pixel region 12a in which a plurality of pixels (not shown) are arranged in a matrix, and a driving voltage can be applied to the liquid crystal for each pixel. ing. When the liquid crystal driving unit 17 applies a driving voltage corresponding to the input image information to each pixel, each pixel is set to a light transmittance corresponding to the image information. Therefore, the light emitted from the light source device 11 is modulated by transmitting through the pixel regions 12a of the liquid crystal light valves 12R, 12G, and 12B, and becomes image light corresponding to image information for each color light. The image light of each color is synthesized for each pixel by a color synthesis optical system (not shown) to become color image light, and then enlarged and projected by the projection lens 13.

  The image information input unit 15 includes a plurality of input terminals (not shown), and various types of image information from an external image supply device (not shown) such as a video playback device or a personal computer are input to these input terminals. Entered. The image information input unit 15 outputs the input image information to the image processing unit 16.

  The image processing unit 16 converts various types of image information input from the image information input unit 15 into image information representing the gradation of each pixel of the liquid crystal light valves 12R, 12G, and 12B, that is, a drive voltage applied to each pixel. Convert to image information for prescription. Further, the image processing unit 16 performs image quality adjustment processing for adjusting the image quality such as brightness, contrast, sharpness, and hue on the converted image information, and sends the processed image information to the liquid crystal driving unit 17. Output.

  The liquid crystal driving unit 17 drives the liquid crystal light valves 12R, 12G, and 12B according to the image information input from the image processing unit 16. Thereby, the light emitted from the light source device 11 is modulated into image light corresponding to the image information by the liquid crystal light valves 12R, 12G, and 12B, and the image light is projected from the projection lens 13.

FIG. 3 is a block diagram illustrating a schematic configuration of the support device 5.
As shown in FIG. 3, the support device 5 includes a control unit 20, a storage unit 21, a remote control 22, a remote control signal reception unit 23, an ultrasonic transmission / reception unit 24, a motor control unit 25, a left and right drive motor 26, and the like. The components other than the remote controller 22 are accommodated in the housing 6 (see FIG. 1).

  The control unit 20 includes a CPU (Central Processing Unit), a RAM (Random Access Memory) used for temporary storage of various data, and the like, and is supported by the CPU operating according to a control program stored in the storage unit 21. The operation of the device 5 is controlled. That is, the control unit 20 functions as a computer together with the storage unit 21.

  The storage unit 21 is configured by a nonvolatile memory such as a flash memory or a mask ROM (Read Only Memory). The storage unit 21 stores a control program for controlling the operation of the support device 5, various setting data for defining operation conditions of the support device 5, and the like.

  The remote controller 22 corresponds to an input operation unit that accepts user input operations, and includes a plurality of operation keys (not shown) for the user to give various instructions to the support device 5. When the user operates various operation keys on the remote controller 22, the remote controller 22 receives this operation and transmits an infrared remote control signal corresponding to the operated operation key.

  The remote control signal receiving unit 23 receives a remote control signal transmitted from the remote control 22 and transmits it to the control unit 20. Then, the control unit 20 performs control based on the remote control signal input from the remote control 22. In addition, it is good also as a structure which uses the operation panel (not shown) attached to the housing | casing 6 instead of the remote control 22 or with the remote control 22 as an input operation part.

  The ultrasonic transmission / reception unit 24 includes a transmission unit and a reception unit (both not shown) configured to include vibrators such as piezoelectric ceramics. Based on the control of the control unit 20, the ultrasonic transmission / reception unit 24 transmits an ultrasonic wave of a predetermined frequency from the transmission unit, receives the reflected wave at the reception unit, and receives the intensity of the received ultrasonic wave (reception intensity). Is output to the control unit 20 as a reception result.

  The motor control unit 25 controls an attitude adjustment mechanism that adjusts the attitude of the projector 1 supported by the support device 5, and specifically, a left and right drive motor 26 for adjusting the horizontal inclination of the projector 1. To control the operation.

4A and 4B are schematic views for explaining the posture adjustment mechanism of the support device 5, wherein FIG. 4A is a side view and FIG. 4B is a plan view.
As shown in FIGS. 4A and 4B, the housing 6 of the support device 5 is fixed to the projector 1 via a support plate 31 that forms the lower surface thereof. The support device 5 includes a fixed plate 32 that is fixed to the ceiling C, and a main shaft 33 that extends downward and is inserted into the inside of the housing 6 is provided at the approximate center of the fixed plate 32. ing. Inside the housing 6, a first gear 34 is fixed to a lower end portion of the main shaft 33 perpendicularly to the main shaft 33, and a second gear 35 is engaged with the first gear 34. The second gear 35 is rotatable about a shaft 36 as a rotation shaft, and a left / right drive motor 26 fixed to the housing 6 is connected to the shaft 36.

  When the second gear 35 is rotated by driving the left and right drive motor 26, the second gear 35 rotates (revolves) around the first gear 34. That is, the housing 6 and the projector 1 fixed to the housing 6 rotate in the left-right direction, that is, the direction in which the image projected on the projection surface S moves left and right, with the main shaft 33 parallel to the vertical direction as the rotation axis. For this reason, the keystone distortion resulting from the inclination of the projector 1 can be corrected by rotating the second gear 35 and adjusting the inclination (angle) of the projector 1. In this specification, the rotation of the projector 1 in which the image projected on the projection surface S moves in the left direction is referred to as left rotation, and the rotation of the projector 1 in which the image moves in the right direction is referred to as right rotation. The tilt of the projector 1 due to the left rotation and the right rotation is referred to as the left-right tilt. A trapezoidal distortion that can be corrected by tilting the projector 1 in the left-right direction is referred to as a horizontal trapezoidal distortion.

  The ultrasonic transmission / reception unit 24 is disposed in front of the main shaft 33 so as to be exposed from the front surface 6f of the housing 6 at the approximate center in the left-right direction, and transmits ultrasonic waves horizontally toward the front and from the front. Receive the reflected wave. Note that a horn 37 is attached to the ultrasonic transmission / reception unit 24 for sharpening directivity and increasing the intensity of ultrasonic waves toward the front. In addition, the ultrasonic transmission / reception unit 24 is fixed directly or indirectly to the housing 6, and the ultrasonic transmission / reception unit 24 rotates integrally with the rotation of the housing 6, that is, the rotation of the projector 1.

  The projector 1 is fixed to the housing 6 so that the optical axis Ax of the projection lens 13 is parallel to the transmission direction of the ultrasonic waves from the ultrasonic transmission / reception unit 24. In this state, the ultrasonic transmission / reception unit 24 is located on a straight line passing through the main shaft 33 that is the rotation center of the housing 6 and parallel to the optical axis Ax of the projection lens 13 in plan view.

Next, the operation of the support device 5 will be described.
The remote controller 22 of the present embodiment includes a projection plane switching key (not shown) for changing the projection plane S to be projected as one of the operation keys. When the user operates the projection plane switching key, the control unit 20 of the support device 5 rotates the projector 1 by 90 degrees in a predetermined direction by the left and right drive motor 26. In addition, the user can rotate the projection plane switching key twice twice in succession by 180 ° and three times in succession, and can rotate any one of the four projection planes S. It can be selected as a projection target.

  When the projection surface S is switched by rotating the projector 1 to the left or right, the optical axis Ax of the projection lens 13 is not perpendicular to the new projection surface S due to the state of the room R, the accuracy of the rotation operation, and the like. The trapezoidal distortion may occur. For this reason, when the key operation is not detected for a predetermined time after the projection plane switching key is operated, the control unit 20 determines that the selection of the projection plane S is completed, and performs a process for correcting the keystone distortion ( Trapezoidal distortion correction processing).

FIG. 5 is a flowchart for explaining the operation of the support device 5 when the projection plane S is switched. When the projection surface switching key of the remote controller 22 is operated by the user, the support device 5 operates according to the flow shown in FIG.
As shown in FIG. 5, first, in step S <b> 1, the control unit 20 of the support device 5 instructs the motor control unit 25 to cause the left and right drive motors 26 to rotate, thereby causing the projector 1 to move 90 in a predetermined direction. Rotate.

  In step S2, the control unit 20 determines whether or not the projection plane switching key has been operated again. When the projection plane switching key is operated, the process returns to step S1 and the projector 1 is further rotated by 90 ° in a predetermined direction. On the other hand, if the projection plane switch key is not operated, the process proceeds to step S3.

  When the process proceeds to step S3 without operating the projection plane switching key, the control unit 20 determines whether or not a predetermined time has elapsed since the projection plane switching key was last operated. And when predetermined time has not passed, it returns to step S2. On the other hand, if the predetermined time has elapsed, the process proceeds to step S4, a trapezoidal distortion correction process described later is performed, and the flow ends.

  In the trapezoidal distortion correction process of the present embodiment, the support device 5 measures the reception intensity of the ultrasonic wave reflected by the projection surface S while changing the attitude (tilt) of the projector 1, and based on the measurement result, the projection lens The posture is adjusted so that the 13 optical axes Ax are perpendicular to the new projection plane S. Since the ultrasonic transmission / reception unit 24 transmits ultrasonic waves parallel to the optical axis Ax of the projection lens 13, the reception intensity of the reflected wave becomes maximum when the optical axis Ax is perpendicular to the projection plane S, and the inclination is large. The smaller it becomes.

FIG. 6 is a flowchart for explaining the trapezoidal distortion correction processing of the present embodiment.
As shown in FIG. 6, in step S <b> 101, the control unit 20 performs various initialization processes for correcting the trapezoidal distortion in the left-right direction. For example, the control unit 20 resets the initial value V ₀ of the measurement result (reception strength) and two variables (normal rotation counter Cf and reverse counter Cr) for controlling the operation to _0, and the projector 1 The rotation direction is set to a predetermined direction (in this embodiment, right rotation).

In step S102, the control unit 20 instructs the ultrasonic transmitting and receiving unit 24 to measure the reception intensity V _n. Specifically, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, and causes the reception unit of the ultrasonic transmission / reception unit 24 to receive the reflected wave and measure the reception intensity V _n . Then, the measured reception intensity V _n is stored in its own RAM. The reception intensity V _n represents the reception intensity measured at the nth time (n is an integer of 1 or more).

In step S103, the control unit 20, a reception strength V _n which is measured this time is compared with the received intensity V _n-1 which is measured last time, receiving current reception strength V _n is the previous intensity V _n-1 It is judged whether it is larger than. If the current reception strength V _n is greater than the previous reception strength V _n−1 (V _n > V _n−1 ), the process proceeds to step S104, where the current reception strength V _n is the previous reception strength V _{n. If n−1} or less (V _n ≦ V _n−1 ), the process proceeds to step S106. After the first (first) measurement, the first measurement result (reception strength V ₁ ) is compared with the initial value V ₀ .

If the current reception intensity is higher than the previous time (V _n > V _n-1 ) and the process proceeds to step S104, the control unit 20 instructs the motor control unit 25 to drive the left and right drive motor 26 to rotate. Then, the projector 1 is rotated by a predetermined unit angle in the set rotation direction. In step S105, the control unit 20 increments the normal rotation counter Cf indicating the number of rotations of the projector 1 in the set rotation direction by one, and returns to step S102.

On the other hand, when the current reception intensity is less than or equal to the previous time (V _n ≦ V _n-1 ) and the process proceeds to step S106, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation, it is reset to left rotation, and if it is set to left rotation, it is reset to right rotation.

  In step S <b> 107, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the newly set rotation direction.

  In step S108, the control unit 20 increments the inversion counter Cr indicating the number of times the rotation direction is inverted by one.

  In step S109, the control unit 20 determines whether or not the product (Cf × Cr) of the normal rotation counter Cf and the reverse rotation counter Cr is greater than 1. If it is 1 or less (Cf × Cr ≦ 1), the process returns to step S102, and if it is greater than 1 (Cf × Cr> 1), the flow ends.

Specifically, the support device 5 of the present embodiment operates as follows according to the above flow. First, since the initial value V ₀ of the reception strength is set to 0, the first reception strength V ₁ is larger than the initial value V ₀ . For this reason, the projector 1 rotates (rotates clockwise) in a preset rotation direction, and the normal rotation counter Cf becomes 1. Next, when the second reception intensity V ₂ is larger than the _first reception intensity V ₁ , the rotation continues to the right and the normal rotation counter Cf becomes 2. Thereafter, while the reception intensity V _n increases, the clockwise rotation continues and the normal counter Cf increases, but the reverse counter Cr remains zero. When the reception intensity V _n becomes smaller at a certain angle, the rotation direction is reversed and the counterclockwise rotation is performed to return to the angle before the reception intensity V _n becomes smaller. At this time, since the reversal counter Cr becomes 1, Cf × Cr> 1 and the process is completed. When the second reception intensity V ₂ is smaller than the _first reception intensity V ₁ , the rotation direction is reversed and the counterclockwise rotation is performed, and the inversion counter Cr becomes 1. At this time, the normal rotation counter Cf is 1, and Cf × Cr = 1, so the process continues. Thereafter, while the reception intensity V _n increases, the counterclockwise rotation counter Cf increases as the counterclockwise rotation continues. Then, when the reception intensity V _n decreases, the rotation direction is reversed and right rotation is performed, and the angle before the reception intensity V _n decreases is restored. At this time, Cf × Cr> 1 and the process ends. With the above operation, the angle of the projector 1 in plan view is the angle at which the reception intensity V _n is maximum, that is, the angle at which the optical axis Ax is perpendicular to the projection plane S, and the trapezoidal distortion in the left-right direction is corrected.

  As described above, according to the projection system 100 of the present embodiment, the following effects can be obtained.

  (1) According to the projection system 100 of the present embodiment, the support device 5 transmits and receives ultrasonic waves while rotating the projector 1, and the optical axis Ax of the projection lens 13 is the projection plane S based on the transmission and reception results. The angle of the projector 1 is adjusted to be vertical. For this reason, it is possible to easily correct the trapezoidal distortion in the left-right direction that may occur with the switching of the projection plane S. Further, since the projector 1 is rotated so that the optical axis Ax of the projection lens 13 is perpendicular to the projection plane S, it becomes possible to correct the trapezoidal distortion without performing image processing, and image degradation due to image processing is prevented. It becomes possible to suppress.

  (2) According to the projection system 100 of the present embodiment, since the inclination of the projector 1 is adjusted based on the change in the reception intensity according to the inclination of the projector 1 with respect to the projection plane S, a set of ultrasonic transmission / reception units 24, and the configuration of the support device 5 can be simplified.

(Second Embodiment)
Hereinafter, the projection system of the second embodiment will be described with reference to the drawings.
The projection system 100 of this embodiment has the same configuration as that of the first embodiment, but the operation of the support device 5 when correcting trapezoidal distortion is different from that of the first embodiment.

FIG. 7 is a flowchart for explaining the trapezoidal distortion correction processing of the present embodiment.
As shown in FIG. 7, in step S201, the control unit 20 performs various initialization processes for correcting the trapezoidal distortion in the left-right direction. For example, the control unit 20 sets the rotation direction of the projector 1 to a predetermined direction (right rotation in the present embodiment).

In step S202, the control unit 20 instructs the ultrasonic transmitting and receiving unit 24 to measure the initial reception intensity V _0. Specifically, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, and causes the reception unit of the ultrasonic transmission / reception unit 24 to receive the reflected wave and measure the reception intensity V ₀ . Then, the measured reception intensity V ₀ is stored in its own RAM.

  In step S203, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

In step S204, the control unit 20 instructs the ultrasonic transmitting and receiving unit 24 to measure the reception strength V ₁ of the post-rotation. Specifically, as in step S202, the control unit 20 transmits an ultrasonic wave from the transmission unit of the ultrasonic transmission / reception unit 24, and causes the reception unit of the ultrasonic transmission / reception unit 24 to receive a reflected wave, thereby receiving the reception intensity V _1. To measure. Then, the measured reception intensity V ₁ is stored in its own RAM.

In step S205, the control unit 20, a reception intensity V ₁ which is measured this time is compared with the received intensity V ₀ the previously measured, or the current reception strength V ₁ is greater than the reception strength V ₀ which last Judge whether or not. If the current reception strength V ₁ is greater than the previous reception strength V ₀ (V ₁ > V ₀ ), the process proceeds to step S207, where the current reception strength V ₁ is equal to or lower than the previous reception strength V ₀ (V _{If 1} ≦ V ₀ ), the process proceeds to step S206.

When the current reception intensity is less than or equal to the previous time (V ₁ ≦ V ₀ ) and the process proceeds to step S206, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation, it is reset to left rotation. As described above, when the current reception intensity is less than or equal to the previous time, the rotation direction is reversed because the angle at which the reception intensity is maximum is in the rotation direction opposite to the current one. On the other hand, when the current reception strength is higher than the previous time, the angle at which the reception strength is maximum is in the current rotation direction, and therefore the rotation direction is maintained as it is.

  In step S207, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

In step S208, the control unit 20, similarly to step S202, and instructs the ultrasonic transmitting and receiving unit 24 to measure the reception intensity V _n after rotation.

In step S209, the control unit 20, a reception strength V _n which is measured this time is compared with the received intensity V _n-1 which is measured last time, receiving current reception strength V _n is the previous intensity V _n-1 It is judged whether it is larger than. If the current reception strength V _n is greater than the previous reception strength V _n−1 (V _n > V _n−1 ), the process returns to step S207, and the current reception strength V _n is the previous reception strength V _{n. When −1} or less (V _n ≦ V _n−1 ), the process proceeds to step S210.

When the current reception intensity is less than or equal to the previous time (V _n ≦ V _n-1 ) and the process proceeds to step S210, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation, it is reset to left rotation, and if it is set to left rotation, it is reset to right rotation.

In step S211, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the newly set rotation direction. Thereby, the angle of the projector 1 returns to the angle before the reception intensity decreases, and the flow ends. With the above operation, the angle of the projector 1 in plan view is the angle at which the reception intensity V _n is maximum, that is, the angle at which the optical axis Ax is perpendicular to the projection plane S, and the trapezoidal distortion in the left-right direction is corrected.

  As described above, according to the projection system 100 of the present embodiment, the same effects as those of the first embodiment can be obtained.

(Third embodiment)
Hereinafter, the projection system of 3rd Embodiment is demonstrated with reference to drawings.
The projection system 100 of this embodiment has the same configuration as that of the first embodiment, but the operation of the support device 5 when correcting the trapezoidal distortion is different from that of the first and second embodiments. Yes. In the first embodiment and the second embodiment, in order to make the optical axis Ax perpendicular to the projection plane S, the angle of the projector 1 is the angle when the maximum reception intensity (maximum reception intensity) is measured. However, in the present embodiment, the angle is an intermediate angle between the two angles at which a predetermined reception intensity smaller than the maximum reception intensity is measured.

FIG. 8 is a diagram showing the directivity of the ultrasonic transmission / reception unit 24 to which the horn 37 is attached. The inclination angle with respect to the transmission direction (0 °) of the ultrasonic wave parallel to the optical axis Ax direction, the attenuation amount of the reception intensity, and It is a graph which shows the relationship.
As shown in FIG. 8, in the vicinity of 0 ° at which the reception strength is maximum, the amount of change in reception strength with respect to the change in angle is small. It is difficult to detect the position accurately. On the other hand, at an angle away from 0 ° (for example, around 30 °), the amount of change in reception intensity with respect to the change in angle becomes large, so that the influence of errors is suppressed. For this reason, the angle of the projector 1 is set to an intermediate angle between two angles at which the reception intensity attenuates at a predetermined rate, so that the optical axis Ax of the projection lens 13 is more accurately perpendicular to the projection plane S. be able to.

FIG. 9 is a flowchart for explaining the trapezoidal distortion correction process of the present embodiment.
As shown in FIG. 9, in step S301, the control unit 20 performs various initialization processes for correcting the trapezoidal distortion in the left-right direction.

In step S302, the control unit 20 causes the reception intensity V _n to be measured while rotating the projector 1 in the left-right direction by a predetermined unit angle within the left-right movable range. For example, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate, and the angle of the projector 1 is set to the angle of the left end in the movable range of the left and right rotation (the projected image is projected onto the projection surface). Angle displayed on the leftmost side of S). Then, the control unit 20 instructs the ultrasonic transmission / reception unit 24 to measure the reception intensity V _n . Thereafter, the control unit 20 causes the projector 1 to rotate the projector 1 to the right by a predetermined unit angle to measure the reception intensity V _n and repeats this until the right end of the movable range is reached.

In step S303, the control unit 20 detects the maximum reception intensity Vmax having the maximum reception intensity from among a plurality of measurement values (reception intensity V _n ) measured within the movable range from the left end to the right end. To do.

In step S304, the control unit 20 specifies the angle of the projector 1 when the reception intensity is 50% of the maximum reception intensity Vmax, based on a plurality of measurement values (reception intensity V _n ) measured within the movable range. To do. The angle at which the reception intensity is 50% of the maximum reception intensity Vmax is specified one on each of the left and right sides of the position (angle) of the maximum reception intensity Vmax.

  In step S305, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate, and rotates the projector 1 so as to be an intermediate angle between the two angles specified in step S304. . With the above operation, the angle of the projector 1 in plan view becomes an angle at which the optical axis Ax is perpendicular to the projection plane S, and the trapezoidal distortion in the left-right direction is corrected.

  As described above, according to the projection system 100 of the present embodiment, in addition to the same effects as those of the first and second embodiments, the following effects can be obtained.

  (1) According to the projection system 100 of the present embodiment, the angle of the projector 1 is adjusted to an intermediate angle between two angles at which the reception intensity is a predetermined value (Vmax × 0.5) smaller than the maximum reception intensity Vmax. Therefore, it is less susceptible to errors during measurement than when adjusting to an angle at which the reception intensity is maximized. For this reason, the optical axis Ax of the projection lens 13 can be more accurately perpendicular to the projection plane S.

  In this embodiment, 50% of the maximum reception strength Vmax is adopted as the predetermined reception strength that is smaller than the maximum reception strength Vmax. However, the predetermined reception strength may be smaller than the maximum reception strength Vmax. It may be 50% or more or 50% or less.

(Fourth embodiment)
Hereinafter, the projection system of 4th Embodiment is demonstrated with reference to drawings.
The projection system 100 of the present embodiment has the same configuration as that of the first embodiment, but the operation of the support device 5 when correcting trapezoidal distortion is different from that of the first to third embodiments. Yes. In the present embodiment, similarly to the third embodiment, the angle of the projector 1 is set to an intermediate angle between two angles at which a predetermined reception intensity smaller than the maximum reception intensity Vmax is measured.

FIG. 10 is a flowchart for explaining the trapezoidal distortion correction processing of the present embodiment.
As shown in FIG. 10, in step S401, the control unit 20 performs various initialization processes for correcting the trapezoidal distortion in the left-right direction. For example, the control unit 20 sets the rotation direction of the projector 1 to a predetermined direction (right rotation in the present embodiment).

In step S402, the control unit 20 instructs the ultrasonic transmitting and receiving unit 24 to measure the initial reception intensity V _0. Specifically, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, and causes the reception unit of the ultrasonic transmission / reception unit 24 to receive the reflected wave and measure the reception intensity V ₀ . Then, the measured reception intensity V ₀ is stored in its own RAM.

  In step S403, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

In step S404, the control unit 20 instructs the ultrasonic transmitting and receiving unit 24 to measure the reception strength V ₁ of the post-rotation. Specifically, as in step S402, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, and causes the reception unit of the ultrasonic transmission / reception unit 24 to receive reflected waves, thereby receiving the reception intensity V _1. To measure. Then, the measured reception intensity V ₁ is stored in its own RAM.

In step S405, the control unit 20, a reception intensity V ₁ which is measured this time is compared with the received intensity V ₀ the previously measured, or the current reception strength V ₁ is greater than the reception strength V ₀ which last Judge whether or not. If the current reception strength V ₁ is greater than the previous reception strength V ₀ (V ₁ > V ₀ ), the process proceeds to step S407, where the current reception strength V ₁ is equal to or lower than the previous reception strength V ₀ (V _{If 1} ≦ V ₀ ), the process proceeds to step S406.

When the current reception intensity is less than or equal to the previous time (V ₁ ≦ V ₀ ) and the process proceeds to step S406, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation, it is reset to left rotation. As described above, when the current reception intensity is less than or equal to the previous time, the rotation direction is reversed because the angle at which the reception intensity is maximum is in the rotation direction opposite to the current one. On the other hand, when the current reception strength is higher than the previous time, the angle at which the reception strength is maximum is in the current rotation direction, and therefore the rotation direction is maintained as it is.

  In step S407, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

In step S408, the control unit 20, similarly to step S402, and instructs the ultrasonic transmitting and receiving unit 24 to measure the reception intensity V _n after rotation.

In step S409, the control unit 20 detects the maximum value (maximum reception intensity Vmax) from the reception intensity V _n measured so far. Specifically, the control unit 20, reception strength V _n measured in step S408 is, if the maximum value of the received intensity V _n, which is measured so far, updating a maximum reception intensity Vmax, the maximum If not, skip this step. When the maximum reception intensity Vmax is updated, the control unit 20 stores the angle of the projector 1 at this time in the RAM together with the maximum reception intensity Vmax.

In step S410, the control unit 20 determines whether or not the reception intensity V _n measured in step S408 is larger than 50% (Vmax × 0.5) of the maximum reception intensity Vmax. If the reception intensity V _n is larger than 50% of the maximum reception intensity Vmax (V _n > Vmax × 0.5), the process returns to step S407 and the above operation is repeated. On the other hand, when the reception intensity V _n is 50% or less of the maximum reception intensity Vmax (V _n ≦ Vmax × 0.5), the process proceeds to step S411. As described above, the control unit 20 continues the rotation of the projector 1 even when the reception intensity V _n decreases after the angle at which the projector 1 reaches the maximum reception intensity Vmax, and the reception intensity V _n is the maximum reception intensity Vmax. The angle of the projector 1 is detected when it becomes 50% of the above.

When the reception intensity V _n is 50% or less of the maximum reception intensity Vmax and the process proceeds to step S411, the control unit 20 stores the current angle C1 of the projector 1 in the RAM.

  In step S412, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate, so that the angle of the projector 1 is the angle at the maximum reception intensity Vmax.

In step S413, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation until then, it resets to left rotation, and if it is set to left rotation, it resets to right rotation. Thereafter, another angle at which the reception intensity V _n becomes 50% of the maximum reception intensity Vmax is detected.

  In step S414, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

In step S415, the control unit 20, similarly to step S402, and instructs the ultrasonic transmitting and receiving unit 24 to measure the reception intensity V _n after rotation.

In step S416, the control unit 20 determines whether or not the reception intensity V _n measured in step S415 is larger than 50% (Vmax × 0.5) of the maximum reception intensity Vmax. If V _n > Vmax × 0.5, the process returns to step S414 and the above operation is repeated. On the other hand, if V _n ≦ Vmax × 0.5, the process proceeds to step S417.

When the reception intensity V _n is 50% or less of the maximum reception intensity Vmax and the process proceeds to step S417, the control unit 20 stores the current angle C2 of the projector 1 in the RAM.

  In step S418, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate, and the angle of the projector 1 is stored as the angle C1 stored in step S411 and the angle stored in step S417. An intermediate angle of C2 (C1 + C2) / 2. With the above operation, the angle of the projector 1 in plan view becomes an angle at which the optical axis Ax is perpendicular to the projection plane S, and the trapezoidal distortion in the left-right direction is corrected.

  As described above, according to the projection system 100 of the present embodiment, the same effects as those of the first to third embodiments can be obtained.

(Fifth embodiment)
Hereinafter, the projection system of 5th Embodiment is demonstrated with reference to drawings.
The projection system 100 of this embodiment has a configuration substantially similar to that of the first embodiment. That is, as shown in FIG. 4, the ultrasonic transmission / reception unit 24 of the support device 5 is in front of the main axis 33 on a straight line passing through the main axis 33 that is the rotation center of the projector 1 and parallel to the optical axis Ax in plan view. It is located on the projection surface S side of the projection target. Then, the ultrasonic transmission / reception unit 24 transmits the ultrasonic waves toward the front in parallel with the optical axis Ax and receives the reflected waves. However, although illustration is omitted, unlike the first embodiment, the ultrasonic transmission / reception unit 24 of the present embodiment is not provided with the horn 37 and the directivity is not sharpened. Similarly to the first embodiment, the ultrasonic transmission / reception unit 24 is directly or indirectly fixed to the casing 6, and the ultrasonic transmission / reception unit 24 is integrated with the rotation of the casing 6, that is, the rotation of the projector 1. Rotate to.

  Since the projection system 100 of the present embodiment is configured as described above, when the support device 5 rotates the projector 1 about the main shaft 33 as a rotation axis in plan view, the ultrasonic transmission / reception unit 24 is also integrated with the projector 1. Rotate. Since the distance between the ultrasonic transmission / reception unit 24 and the projection plane S changes due to the rotation of the projector 1 (change in angle), the time from the transmission of the ultrasonic wave from the transmission unit to the reception by the reception unit (arrival time) ) Will also change.

  For this reason, the support device 5 of the present embodiment measures the arrival time of the ultrasonic wave reflected on the projection surface S while changing the attitude (tilt) of the projector 1, and based on the measurement result, the light of the projection lens 13 is measured. The posture is adjusted so that the axis Ax is perpendicular to the projection plane S. When the optical axis Ax is perpendicular to the projection plane S, the distance between the projection plane S and the ultrasonic transmission / reception unit 24 is the shortest (minimum), so the arrival time of the ultrasonic wave is the shortest (minimum). As the inclination increases, the distance between the projection plane S and the ultrasonic transmission / reception unit 24 increases, and the arrival time is delayed.

  FIG. 11 is a flowchart for explaining the trapezoidal distortion correction processing of the present embodiment. The same operation as in the first embodiment is performed except that the arrival time is measured instead of the ultrasonic reception intensity and the posture is adjusted based on the arrival time.

As shown in FIG. 11, in step S501, the control unit 20 performs various initialization processes for correcting the trapezoidal distortion in the left-right direction. For example, the control unit 20 resets the initial value T ₀ of the measurement result (arrival time) and the two variables (normal rotation counter Cf and reverse counter Cr) for controlling the operation to _0, and the projector 1 The rotation direction is set to a predetermined direction (in this embodiment, right rotation).

At step S502, the control unit 20 to perform the transmission and reception of ultrasonic waves to the ultrasonic transmitting and receiving unit 24 to measure the ultrasonic wave arrival time T _n. Specifically, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, causes the reception unit of the ultrasonic transmission / reception unit 24 to receive reflected waves, and transmits the time required for transmission to reception (arrival). Time) _Tn is measured. Then, the measured arrival time T _n is stored in its own RAM. The arrival time T _n represents the arrival time measured n times (n is an integer of 1 or more).

At step S503, the control unit 20, and the currently measured arrival time T _n, it is compared with the arrival time T _n-1 which is measured last time, this arrival time T _n is the last arrival time T _n-1 It is judged whether it is shorter than. Then, this arrival time T _n is less than T _n-1 preceding the arrival time (T _n <T _n-1) proceeds to step S504 if this time the arrival time T _n is the last arrival time T _{If n−1} or more (T _n ≧ T _n−1 ), the process proceeds to step S506. After the first (first) measurement, the first measurement result (arrival time T ₁ ) is compared with the initial value T ₀ .

If the current arrival time is shorter than the previous time (T _n <T _n-1 ) and the process proceeds to step S504, the control unit 20 instructs the motor control unit 25 to rotate the left and right drive motor 26. Then, the projector 1 is rotated by a predetermined unit angle in the set rotation direction. In step S505, the control unit 20 increments the normal rotation counter Cf indicating the number of times the projector 1 has been rotated in the set rotation direction by one, and returns to step S502.

On the other hand, if the current arrival time is _{equal to} or longer than the previous time (T _n ≧ T _n-1 ) and the process proceeds to step S506, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation, it is reset to left rotation, and if it is set to left rotation, it is reset to right rotation.

  In step S507, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the newly set rotation direction.

  In step S508, the control unit 20 increments the inversion counter Cr indicating the number of times the rotation direction is inverted by one.

In step S509, the control unit 20 determines whether or not the product (Cf × Cr) of the normal rotation counter Cf and the reverse counter Cr is greater than 1. If 1 or less (Cf × Cr ≦ 1), the process returns to step S502, and if it is greater than 1 (Cf × Cr> 1), the flow ends. With the above operation, the angle of the projector 1 in the plan view becomes an angle at which the arrival time T _n is the shortest, that is, an angle at which the optical axis Ax is perpendicular to the projection plane S, and the trapezoidal distortion in the left-right direction is corrected.

  As described above, according to the projection system 100 of the present embodiment, in addition to the effect (1) of the first embodiment, the following effects can be obtained.

  (1) According to the projection system 100 of the present embodiment, since the inclination of the projector 1 is adjusted based on the change in the arrival time according to the inclination of the projector 1 with respect to the projection plane S, a set of ultrasonic transmission / reception units 24, and the configuration of the projector 1 can be simplified.

  In the present embodiment, the larger the distance between the main shaft 33 that is the center of rotation and the ultrasonic transmission / reception unit 24, that is, the larger the rotation radius of the ultrasonic transmission / reception unit 24, is, The amount of change in the distance from the projection surface S increases, and the influence of errors during measurement can be reduced. For this reason, it is desirable that the rotation radius of the ultrasonic transmission / reception unit 24 be as large as possible.

(Sixth embodiment)
Hereinafter, the projection system of 6th Embodiment is demonstrated with reference to drawings.
The projection system 100 of this embodiment has the same configuration as that of the fifth embodiment, but the operation of the support device 5 when correcting trapezoidal distortion is different from that of the fifth embodiment.

  FIG. 12 is a flowchart for explaining the trapezoidal distortion correction processing of the present embodiment. Note that the same operation as in the second embodiment is performed except that the arrival time is measured instead of the ultrasonic reception intensity and the posture is adjusted based on the arrival time.

  As shown in FIG. 12, in step S601, the control unit 20 performs various initialization processes for correcting the trapezoidal distortion in the left-right direction. For example, the control unit 20 sets the rotation direction of the projector 1 to a predetermined direction (right rotation in the present embodiment).

In step S602, the control unit 20, the ultrasonic transmitting and receiving unit 24 to perform the transmission and reception of ultrasonic waves, it measures the initial arrival time T _0. Specifically, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, causes the reception unit of the ultrasonic transmission / reception unit 24 to receive reflected waves, and transmits the time required for transmission to reception (arrival). Time) T ₀ is measured. Then, the measured arrival time T ₀ is stored in its own RAM.

  In step S <b> 603, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

At step S604, the control unit 20 instructs the ultrasonic transmitting and receiving unit 24 to measure the arrival time T ₁ of the post-rotation. Specifically, as in step S602, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, and causes the reception unit of the ultrasonic transmission / reception unit 24 to receive reflected waves, thereby reaching the arrival time T _1. Measure. Then, the measured arrival time T ₁ is stored in its own RAM.

At step S605, the control unit 20, an arrival time T ₁ which is measured this time is compared with the arrival time T ₀ the previously measured, or the current arrival time T ₁ is less than T ₀ preceding the arrival time Judge whether or not. If the current arrival time T ₁ is shorter than the previous arrival time T ₀ (T ₁ <T ₀ ), the process proceeds to step S607, where the current arrival time T ₁ is equal to or greater than the previous arrival time T ₀ (T _{If 1} ≧ T ₀ ), the process proceeds to step S606.

When the current arrival time is equal to or longer than the previous time (T ₀ ≧ T ₁ ) and the process proceeds to step S606, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation, it is reset to left rotation. Thus, when the current arrival time is equal to or longer than the previous time, the rotation direction is reversed because the angle at which the arrival time is the shortest is in the rotation direction opposite to the current time. On the other hand, when the current arrival time is shorter than the previous time, the rotation direction is maintained as it is because the angle at which the arrival time is the shortest is in the current rotation direction.

  In step S <b> 607, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

At step S608, the control unit 20, similarly to step S602, and to perform the transmission and reception of ultrasonic waves to the ultrasonic transmitting and receiving unit 24, and measures the arrival time T _n after rotation.

In step S609, the control unit 20, and the currently measured arrival time T _n, it is compared with the arrival time T _n-1 which is measured last time, this arrival time T _n is the last arrival time T _n-1 It is judged whether it is shorter than. If the current arrival time T _n is shorter than the previous arrival time T _n−1 (T _n <T _n−1 ), the process returns to step S607, and the current arrival time T _n is the previous arrival time T _{n. When −1} or more (T _n ≧ T _n-1 ), the process proceeds to step S610.

When the current arrival time is _{equal to} or longer than the previous time (T _n ≧ T _n-1 ) and the process proceeds to step S610, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation, it is reset to left rotation, and if it is set to left rotation, it is reset to right rotation.

In step S611, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motors 26 to rotate, and rotates the projector 1 by a predetermined unit angle in the newly set rotation direction. Thereby, the angle of the projector 1 returns to the angle before the arrival time is increased, and the flow ends. With the above operation, the angle of the projector 1 in the plan view becomes an angle at which the arrival time T _n is the shortest, that is, an angle at which the optical axis Ax is perpendicular to the projection plane S, and the trapezoidal distortion in the left-right direction is corrected.

  As described above, according to the projection system 100 of this embodiment, the same effect as that of the fifth embodiment can be obtained.

(Seventh embodiment)
Hereinafter, the projection system of 7th Embodiment is demonstrated with reference to drawings.
The projection system 100 of the present embodiment has the same configuration as that of the fifth embodiment, but the operation of the support device 5 when correcting the trapezoidal distortion is different from that of the fifth and sixth embodiments. Yes. In the fifth embodiment and the sixth embodiment, in order to make the optical axis Ax perpendicular to the projection plane S, the angle of the projector 1 is the angle when the shortest arrival time (shortest arrival time) is measured. However, in this embodiment, the angle is an intermediate angle between two angles at which a predetermined arrival time longer than the shortest arrival time is measured.

  Here, when the angle of the optical axis Ax with respect to the projection plane S is near the vertical, that is, near the angle at which the arrival time is the shortest, the amount of change in the distance between the projection plane S and the ultrasonic transmission / reception unit 24 with respect to the change in angle, Since the change amount of the arrival time is small, it is easily affected by an error when the arrival time is measured, and it is difficult to accurately detect the angle at which the arrival time is the shortest. On the other hand, when the angle of the optical axis Ax with respect to the projection plane S is away from the vertical, the amount of change in the distance between the projection plane S and the ultrasonic transmission / reception unit 24 with respect to the change in angle, that is, the amount of change in arrival time increases. The influence of error is suppressed. For this reason, the optical axis Ax of the projection lens 13 is set to the projection plane S by setting the angle of the projector 1 to an intermediate angle between the two angles when the predetermined arrival time longer than the shortest arrival time is measured. Can be more accurately vertical.

  FIG. 13 is a flowchart for explaining the trapezoidal distortion correction processing of the present embodiment. The same operation as in the third embodiment is performed except that the arrival time is measured instead of the ultrasonic reception intensity and the posture is adjusted based on the arrival time.

  As shown in FIG. 13, in step S701, the control unit 20 performs various initialization processes for correcting the trapezoidal distortion in the left-right direction.

In step S702, the control unit 20, while rotating in the horizontal direction of the projector 1 by a predetermined unit angle in the left and right movable range, to measure the arrival time T _n. For example, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate, and the angle of the projector 1 is set to the angle of the left end in the movable range of the left and right rotation (the projected image is projected onto the projection surface). Angle displayed on the leftmost side of S). Then, the control unit 20 measures the arrival time T _n by performing the transmission and reception of ultrasonic waves to the ultrasonic transmitting and receiving unit 24. Thereafter, the control unit 20, the projector 1 is only right rotation a predetermined unit angle by the left and right driving motor 26 performs a measurement of the arrival time T _n, a repeated until reaching the right end of the movable range.

In step S703, the control unit 20 detects the shortest arrival time Tmin with the shortest arrival time from a plurality of measurement values (arrival time _Tn ) measured within the movable range from the left end to the right end. To do.

In step S704, the control unit 20 calculates a time (Tmin + α) obtained by adding a predetermined time α to the shortest arrival time Tmin based on a plurality of measurement values (arrival time T _n ) measured within the movable range. The angle of the projector 1 when it becomes is specified. The angle at which the arrival time becomes Tmin + α is specified one on each of the left and right sides of the position (angle) of the shortest arrival time Tmin.

  In step S705, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 so that the angle is an intermediate value between the two angles specified in step S704. . With the above operation, the angle of the projector 1 in plan view becomes an angle at which the optical axis Ax is perpendicular to the projection plane S, and the trapezoidal distortion in the left-right direction is corrected.

  As described above, according to the projection system 100 of the present embodiment, the following effects can be obtained in addition to the same effects as those of the fifth and sixth embodiments.

  (1) According to the projection system 100 of the present embodiment, the angle of the projector 1 is adjusted to an intermediate angle between two angles at which the arrival time is a predetermined value (Tmin + α) that is greater than the shortest arrival time Tmin. It is less susceptible to errors during measurement than when adjusting to an angle that minimizes the arrival time. For this reason, the optical axis Ax of the projection lens 13 can be more accurately perpendicular to the projection plane S.

(Eighth embodiment)
Hereinafter, the projection system of 8th Embodiment is demonstrated with reference to drawings.
The projection system 100 of this embodiment has the same configuration as that of the fifth embodiment, but the operation of the support device 5 when correcting trapezoidal distortion is different from that of the fifth to seventh embodiments. Yes. In the present embodiment, similarly to the seventh embodiment, the angle of the projector 1 is an intermediate angle between two angles at which a predetermined arrival time longer than the shortest arrival time Tmin is measured.

  FIG. 14 is a flowchart for explaining the trapezoidal distortion correction processing of the present embodiment. The same operation as in the fourth embodiment is performed except that the arrival time is measured instead of the ultrasonic reception intensity and the posture is adjusted based on the arrival time.

  As shown in FIG. 14, in step S801, the control unit 20 performs various initialization processes for correcting the trapezoidal distortion in the left-right direction. For example, the control unit 20 sets the rotation direction of the projector 1 to a predetermined direction (right rotation in the present embodiment).

At step S802, the control unit 20, the ultrasonic transmitting and receiving unit 24 to perform the transmission and reception of ultrasonic waves, it measures the initial arrival time T _0. Specifically, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, and causes the reception unit of the ultrasonic transmission / reception unit 24 to receive reflected waves and measures the arrival time T ₀ . Then, the measured arrival time T ₀ is stored in its own RAM.

  In step S <b> 803, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

At step S804, the control unit 20, by transmitting and receiving ultrasonic waves to the ultrasonic transmitting and receiving unit 24 to measure the arrival time T ₁ of the post-rotation. Specifically, as in step S802, the control unit 20 causes the transmission unit of the ultrasonic transmission / reception unit 24 to transmit ultrasonic waves, and causes the reception unit of the ultrasonic transmission / reception unit 24 to receive reflected waves, thereby reaching the arrival time T _1. Measure. Then, the measured arrival time T ₁ is stored in its own RAM.

At step S805, the control unit 20, an arrival time T ₁ which is measured this time is compared with the arrival time T ₀ the previously measured, or the current arrival time T ₁ is less than T ₀ preceding the arrival time Judge whether or not. If the current arrival time T ₁ is shorter than the previous arrival time T ₀ (T ₁ <T ₀ ), the process proceeds to step S807, where the current arrival time T ₁ is equal to or longer than the previous arrival time T ₀ (T _{If 1} ≧ T ₀ ), the process proceeds to step S806.

If the current arrival time is greater than or equal to the previous time (T ₁ ≧ T ₀ ) and the process proceeds to step S806, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation, it is reset to left rotation. Thus, when the current arrival time is equal to or longer than the previous time, the rotation direction is reversed because the angle at which the arrival time is the shortest is in the rotation direction opposite to the current time. On the other hand, when the current arrival time is shorter than the previous time, the rotation direction is maintained as it is because the angle at which the arrival time is the shortest is in the current rotation direction.

  In step S807, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate, and rotates the projector 1 by a predetermined unit angle in the set rotation direction.

In step S808, as in step S802, the control unit 20 causes the ultrasonic transmission / reception unit 24 to transmit / receive ultrasonic waves, and measures the arrival time T _n after rotation.

In step S809, the control unit 20 detects the minimum value (minimum arrival time Tmin) from the hitherto arrival time T _n that is measured. Specifically, the control unit 20, arrival time T _n measured in step S808 is, if the minimum value of the arrival time which has been measured T _n so far, and updates the shortest arrival time Tmin, the minimum If not, skip this step. When the shortest arrival time Tmin is updated, the control unit 20 stores the angle of the projector 1 at this time in the RAM together with the shortest arrival time Tmin.

In step S810, the control unit 20 determines whether shorter or not than the time measured arrival time T _n is obtained by adding a predetermined time alpha shortest arrival time Tmin at step S808 (Tmin + α). If the arrival time T _n is shorter than Tmin + α, the process returns to step S807 and the above operation is repeated. On the other hand, if the arrival time T _n is _equal to or longer than Tmin + α, the process proceeds to step S811. Thus, the control unit 20, past the angle of the angle of the projector 1 is the shortest arrival time Tmin continued rotation of the projector 1 also arrival time T _n is been increasing, when the arrival time T _n is Tmin + alpha The angle of the projector 1 is detected.

When the arrival time T _n is longer than Tmin + α and the process proceeds to step S811, the control unit 20 stores the current angle C1 of the projector 1 in the RAM.

  In step S812, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate, so that the angle of the projector 1 is the angle at the shortest arrival time Tmin.

In step S813, the control unit 20 reverses the set rotation direction. That is, if it is set to right rotation until then, it resets to left rotation, and if it is set to left rotation, it resets to right rotation. Thereafter, another angle is detected at which the arrival time T _n becomes a time (Tmin + α) obtained by adding a predetermined time α to the shortest arrival time Tmin.

  In step S814, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate and rotate the projector 1 by a predetermined unit angle in the set rotation direction.

In step S815, the control unit 20, similarly to step S802, the made to perform transmission and reception of ultrasonic waves to the ultrasonic transmitting and receiving unit 24, and measures the arrival time T _n after rotation.

In step S 816, the control unit 20 determines whether shorter or not than the time measured arrival time T _n is obtained by adding a predetermined time alpha shortest arrival time Tmin at step S815 (Tmin + α). If the arrival time T _n is shorter than Tmin + α, the process returns to step S814 and the above operation is repeated. On the other hand, if the arrival time T _n is _equal to or greater than Tmin + α, the process proceeds to step S817.

When the arrival time T _n is longer than Tmin + α and the process proceeds to step S817, the control unit 20 stores the current angle C2 of the projector 1 in the RAM.

  In step S818, the control unit 20 instructs the motor control unit 25 to cause the left and right drive motor 26 to rotate, and the angle of the projector 1 is stored as the angle C1 stored in step S811 and the angle stored in step S817. An intermediate angle of C2 (C1 + C2) / 2. With the above operation, the angle of the projector 1 in plan view becomes an angle at which the optical axis Ax is perpendicular to the projection plane S, and the trapezoidal distortion in the left-right direction is corrected.

  As described above, according to the projection system 100 of the present embodiment, the same effects as those of the fifth to seventh embodiments can be obtained.

  In this specification, the housing 6 including the support plate 31 corresponds to a support unit, the ultrasonic transmission / reception unit 24 corresponds to a transmission / reception unit, the left / right drive motor 26 corresponds to a drive unit, and steps S1 to S3 are performed. The control unit 20 at the time of execution corresponds to the projection plane switching unit, and the control unit 20 at the time of executing step S4 (trapezoidal distortion correction processing) corresponds to the adjustment unit. Further, in the present specification, the plan view means viewing from the up-down direction, that is, the rotation axis direction of the left-right rotation.

(Modification)
Moreover, you may change the said embodiment as follows.

  In the above-described embodiment, the configuration in which the ultrasonic transmission / reception unit 24 is accommodated in the housing 6 has been described. However, the arrangement of the ultrasonic transmission / reception unit 24 is not limited thereto, and for example, the ultrasonic transmission / reception unit 24 is connected to the housing 6. You may make it arrange | position outside.

  In the above embodiment, the projector 1 is mounted on the ceiling C using the support device 5. However, the projector 1 may be turned upside down and installed on a table or the like.

  In the above embodiment, the ultrasonic transmission / reception unit 24 is directly or indirectly fixed to the housing 6 and rotates with the housing 6. However, at least the ultrasonic transmission / reception unit 24 and the projector 1 are integrated. If it is the structure which rotates automatically, it will not be limited to this aspect.

  In the fifth to eighth embodiments, the ultrasonic transmission / reception unit 24 is in front of the main shaft 33 (projection target) on a straight line passing through the main shaft 33 that is the rotation center of the projector 1 and parallel to the optical axis Ax in plan view. Therefore, when the optical axis Ax of the projection lens 13 is perpendicular to the projection plane S, the arrival time of the ultrasonic wave becomes the shortest. On the other hand, if the ultrasonic transmission / reception unit 24 is positioned behind the main axis 33 (on the opposite side of the projection surface S to be projected) on a straight line passing through the main axis 33 and parallel to the optical axis Ax, the projection lens When the optical axis Ax of 13 is perpendicular to the projection plane S, the arrival time of the ultrasonic wave becomes the longest. Therefore, in this case, the angle of the projector 1 is adjusted to an angle at which the arrival time is the longest (longest arrival time Tmax), or a predetermined arrival time (Tmax−α that is shorter than the longest arrival time Tmax). ) May be adjusted to an intermediate angle between the two angles.

  In the above embodiment, the trapezoidal distortion correction process is performed when the projection plane switching key has not been operated for a predetermined time. However, after the operation of switching the projection plane S is performed, the keystone distortion correction is performed on the remote controller 22. The trapezoidal distortion correction process may be performed when an operation for instructing is performed.

  In the above embodiment, an ultrasonic wave is used as a transmission wave for adjusting the angle of the projector 1, but a sound wave other than the ultrasonic wave may be used, or light and radio waves may be used. Is also possible. However, in the aspect in which the angle is adjusted based on the change in the reception intensity, it is desirable that the transmission wave has high directivity. For this reason, when using radio waves, it is desirable to use microwaves with short wavelengths. Further, in the aspect in which the angle is adjusted based on the change in arrival time, using a transmission wave having a slower propagation speed is less susceptible to errors, and accurate adjustment can be performed with an inexpensive configuration.

  In the above embodiment, the three-plate projector 1 using the three liquid crystal light valves 12R, 12G, and 12B as the light modulation device has been described. However, the present invention is not limited to this. For example, a mode in which each pixel is modulated into image light by a single liquid crystal light valve including sub-pixels that can transmit R light, G light, and B light can be employed.

  In the above-described embodiment, the transmissive liquid crystal light valves 12R, 12G, and 12B are used as the light modulator, but a reflective light modulator such as a reflective liquid crystal light valve can also be used. In addition, it is possible to use a micromirror array device that modulates light emitted from a light source by controlling the emission direction of incident light for each micromirror as a pixel.

  In the above embodiment, the light source device 11 is constituted by the discharge-type light source lamp 11a. However, the light source device 11 may be applied to a solid light source such as an LED (Light Emitting Diode) light source or a laser light source, or other light sources. it can.

  DESCRIPTION OF SYMBOLS 1 ... Projector, 2 ... Housing | casing, 2f ... Front surface, 5 ... Supporting device, 6 ... Housing | casing, 6f ... Front surface, 10 ... Image projection part, 11 ... Light source device, 11a ... Light source lamp, 11b ... Reflector, 12R, 12G , 12B ... liquid crystal light valve, 12a ... pixel area, 13 ... projection lens, 15 ... image information input unit, 16 ... image processing unit, 17 ... liquid crystal drive unit, 20 ... control unit, 21 ... storage unit, 22 ... remote control, DESCRIPTION OF SYMBOLS 23 ... Remote control signal receiving part, 24 ... Ultrasonic transmission / reception part, 25 ... Motor control part, 26 ... Left-right drive motor, 31 ... Support plate, 32 ... Fixed plate, 33 ... Main shaft, 34 ... First gear, 35 ... First 2 gears, 36 ... shaft, 37 ... horn, 100 ... projection system, Ax ... optical axis, C ... ceiling, R ... room, S ... projection plane.

Claims (19)

A support unit that supports a projector that projects image light based on image information from a projection optical system onto a projection surface;
A transmission / reception unit for transmitting a predetermined transmission wave to the projection surface and receiving the transmission wave reflected by the projection surface;
A drive unit that rotates the projector integrally with the transmission / reception unit;
The drive unit causes the transmission / reception unit to transmit / receive the transmission wave while rotating the projector, and based on the result of the transmission / reception, the drive so that the optical axis of the projection optical system is perpendicular to the projection plane An adjusting unit for adjusting the angle of the projector by a unit;
A support device comprising: The support device according to claim 1,
A projection plane switching unit that rotates the projector by the drive unit and switches the projection plane;
The support device, wherein the adjustment unit adjusts an angle of the projector after the projection plane switching unit switches the projection plane. The support device according to claim 1 or 2,
The adjustment unit adjusts an angle of the projector based on a change in reception intensity of the transmission wave. The support device according to claim 3,
The transmission / reception unit transmits the transmission wave toward the projection plane in parallel with the optical axis of the projection optical system,
The adjustment unit adjusts the angle of the projector to an angle at which the reception intensity becomes maximum. The support device according to claim 3,
The transmission / reception unit transmits the transmission wave toward the projection plane in parallel with the optical axis of the projection optical system,
The adjustment unit adjusts the angle of the projector to an intermediate angle between two angles at which the reception intensity is a predetermined value smaller than a maximum value. The support device according to any one of claims 3 to 5,
The support device, wherein the transmission / reception unit is located on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the driving unit. The support device according to claim 1 or 2,
The adjustment unit adjusts an angle of the projector based on a change in arrival time of the transmission wave. The support device according to claim 7,
The transmission / reception unit is positioned on the projection plane side with respect to the rotation axis on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the drive unit. And
The adjustment device adjusts the angle of the projector to an angle that minimizes the arrival time. The support device according to claim 7,
The transmission / reception unit is positioned on the projection plane side with respect to the rotation axis on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the drive unit. And
The adjusting device adjusts the angle of the projector to an intermediate angle between two angles at which the arrival time is a predetermined value larger than a minimum value.   A projection system comprising the support device according to claim 1 and the projector. A support unit that supports a projector that projects image light based on image information from a projection optical system onto a projection surface;
A transmission / reception unit for transmitting a predetermined transmission wave to the projection surface and receiving the transmission wave reflected by the projection surface;
A drive unit that rotates the projector integrally with the transmission / reception unit;
A method of controlling a support device comprising:
The drive unit causes the transmission / reception unit to transmit / receive the transmission wave while rotating the projector, and based on the result of the transmission / reception, the drive so that the optical axis of the projection optical system is perpendicular to the projection plane An adjustment step of adjusting the angle of the projector by a unit;
A control method for a support device, comprising: It is a control method of the supporting device according to claim 11, Comprising:
A projection plane switching step of switching the projection plane by rotating the projector by the drive unit;
In the adjusting step, the angle of the projector is adjusted after the projection plane is switched in the projection plane switching step. A control method for a support device according to claim 11 or 12,
In the adjusting step, the angle of the projector is adjusted based on a change in received intensity of the transmission wave. It is a control method of the supporting device according to claim 13,
The transmission / reception unit transmits the transmission wave toward the projection plane in parallel with the optical axis of the projection optical system,
In the adjusting step, the angle of the projector is adjusted to an angle that maximizes the reception intensity. It is a control method of the supporting device according to claim 13,
The transmission / reception unit transmits the transmission wave toward the projection plane in parallel with the optical axis of the projection optical system,
In the adjusting step, the angle of the projector is adjusted to an intermediate angle between two angles at which the reception intensity is a predetermined value smaller than a maximum value. It is a control method of a supporting device according to any one of claims 13 to 15,
The method of controlling a support device, wherein the transmission / reception unit is positioned on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the drive unit . A control method for a support device according to claim 11 or 12,
In the adjusting step, the angle of the projector is adjusted based on a change in arrival time of the transmission wave. A control method for a support device according to claim 17,
The transmission / reception unit is positioned on the projection plane side with respect to the rotation axis on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the drive unit. And
In the adjusting step, the angle of the projector is adjusted to an angle that minimizes the arrival time. A control method for a support device according to claim 17,
The transmission / reception unit is positioned on the projection plane side with respect to the rotation axis on a straight line passing through the rotation axis and parallel to the optical axis of the projection optical system when viewed from the rotation axis direction of rotation by the drive unit. And
In the adjusting step, the angle of the projector is adjusted to an intermediate angle between two angles at which the arrival time is a predetermined value larger than a minimum value.

Images