JP7087391B2 - Image display device and its control method - Google Patents

Description

The present invention relates to an image display device and a control method thereof.

Patent Document 1 describes a so-called interactive projector that emits a planar detection light along a projection surface and identifies the position of the indicator by detecting the detection light reflected by the indicator such as a pen or a finger. Has been done.
The projector described in Patent Document 1 projects an image that assists in adjusting the direction of the detected light based on the detected light reflected by the jig arranged on the projection surface by the user. The user adjusts the direction of the detected light while looking at the image.

JP-A-2015-159529

In the projector described in Patent Document 1, when adjusting the direction of the detected light, the user must arrange a jig on the projection surface, so that the adjustment work is complicated.

The present invention has been made in view of the above circumstances, and provides a technique capable of reducing the complexity of the work of adjusting the direction of the detected light as compared with the case where the user arranges the jig on the projection surface. Is the solution issue.

One aspect of the image display device according to the present invention is a display unit that displays an image on the display surface, an emission unit that emits light, and a change unit that changes the angle of the light emitted from the emission unit with respect to the display surface. It is characterized by including a position detection unit that detects a reflection position where the emitted light of the emission unit is reflected, and a change control unit that controls the change unit based on the detection result of the position detection unit. do.
According to this aspect, the angle of the light emitted from the emitting unit with respect to the display surface is changed based on the detection result of the reflection position of the emitted light of the emitting unit. Therefore, the complexity of the adjustment work can be reduced as compared with the case where the user arranges the jig on the display surface and adjusts the direction of the light emitted from the injection unit.

In one aspect of the image display device described above, the change unit includes a drive unit and an adjustment mechanism that changes the angle according to the drive of the drive unit, and the change control unit is a position detection unit. It is desirable to control the drive of the drive unit based on the detection result. According to this aspect, the angle of the light emitted from the emitting unit with respect to the display surface can be automatically adjusted by controlling the driving of the driving unit.

In one aspect of the image display device described above, even if the change control unit controls the drive of the drive unit, the position detection unit sandwiches the image on the display surface and the target is on the opposite side of the injection unit. When the position is not detected as the reflection position, the target drive amount for moving the reflection position to the target position is determined based on the relationship between the drive amount of the drive unit and the movement amount of the reflection position. It is desirable to drive the drive unit by the target drive amount. According to this aspect, for example, even if the position detection unit cannot detect the target position as the reflection position even if the change control unit controls the drive of the drive unit due to the weak reflected light, the reflection position is moved to the target position. It will be possible.

In one aspect of the image display device described above, the change control unit drives the drive unit when the position detection unit does not detect the target position as the reflection position even if the drive unit is controlled. It is desirable to measure the relationship based on the detection result of the position detection unit when the vehicle is moved, and to determine the target drive amount based on the measured relationship. According to this aspect, since the target drive amount is determined based on the actual relationship between the drive of the drive unit and the movement amount of the reflection position, the target drive amount can be determined with high accuracy.

In one aspect of the image display device described above, in the change control unit, when the position detection unit detects the reflection position when the drive unit is driven by the target drive amount, the position detection unit causes the change control unit. It is desirable to control the drive of the drive unit until the reflection position is no longer detected.
It is conceivable that a convex portion such as a frame exists in a region on the opposite side of the image on the display surface from the ejection portion. In this case, when the reflection position is moved to the target position, the position detecting unit may detect the reflection position on the convex portion, and this reflection position may be mistaken for the reflection position by the indicator.
According to this aspect, when the reflection position is detected when the drive unit is driven by the target drive amount, the drive of the drive unit is controlled until the reflection position is not detected. Therefore, the reflection position at the convex portion described above is used. Can be less likely to be mistaken for the reflection position on the indicator.

In one aspect of the image display device described above, even if the change control unit controls the change unit, the position detection unit sandwiches the image on the display surface and sets a target position on the opposite side of the injection unit. When it is not detected as the reflection position, it is desirable that the amount of light emitted from the emission portion is larger than the amount of light at that time. According to this aspect, for example, the amount of light emitted from the emission unit when the position detection unit cannot detect the target position as the reflection position even if the change control unit controls the change unit because the reflected light is weak. Can be made larger than the amount of light at that time, and it becomes easier to detect the reflection position.

In one aspect of the image display device described above, an image pickup unit that captures an image of the display surface to generate an image capture image is further included, and the position detection unit detects the reflection position based on the image pickup image and controls the change. If the position detection unit does not detect the target position on the display surface opposite to the injection unit as the reflection position even if the change unit is controlled, the image pickup unit may be used. It is desirable to make the sensitivity of the above higher than the sensitivity at that time. According to this aspect, for example, when the position detection unit cannot detect the target position as the reflection position even if the change control unit controls the change unit because the reflected light is weak, the sensitivity of the image pickup unit is higher than the sensitivity at that time. It can be raised, making it easier to detect the reflection position.

One aspect of the control method of the image display device according to the present invention is to change the angle between the display unit that displays an image on the display surface, the emission unit that emits light, and the light emitted from the emission unit with respect to the display surface. It is a control method of an image display device having a change part, and controls the change part based on a step of detecting a reflection position where the emitted light of the emission part is reflected and a detection result of the reflection position. It is characterized by including steps to be performed. According to this aspect, it is possible to reduce the complexity of the adjustment work as compared with the case where the user arranges the jig on the display surface and adjusts the direction of the light emitted from the injection unit.

It is a figure which shows typically the image display device 1 which concerns on 1st Embodiment. It is a side view of the image display device 1 seen from the direction of the arrow P shown in FIG. It is a figure which showed the projector 2 and the light curtain generation apparatus 3. It is a figure which showed the adjustment direction of a laser light source unit 31. It is a flowchart for demonstrating operation. It is a figure which showed the state which the light curtain L was located at the maximum position in the θ direction. It is a figure which showed an example of the screen SC which provided the convex part H in the region R. It is a figure which showed the captured image U1 when the 1st position E1 is on the projected image P1. It is a figure which showed the captured image U2 when the light curtain L is the minimum position in the θ direction. It is a figure which showed the captured image U3 when the line formed by the reflection position E was made parallel to the lower end L1. It is a figure which showed the captured image U4 when the reflection position E is located at the target position D. It is a figure which shows the modification 4 schematically.

Hereinafter, embodiments according to the present invention will be described with reference to the drawings. In the drawings, the dimensions and scale of each part may differ from the actual ones. Moreover, the embodiment described below is a suitable specific example of the present invention. For this reason, the present embodiment is provided with various technically preferable limitations. However, the scope of the present invention is not limited to these forms unless it is stated in the following description that the present invention is particularly limited.

<First Embodiment>
FIG. 1 is a diagram schematically showing an image display device 1 according to the first embodiment. FIG. 2 is a side view of the image display device 1 as seen from the direction of the arrow P shown in FIG.
The image display device 1 includes a projector 2, a light curtain generation device 3, and an image pickup unit 21. In FIG. 2, the image pickup unit 21 is shown as hardware integrated with the projector 2. The image pickup unit 21 may communicate with the projector 2 by wire or wirelessly without being integrated with the projector 2.

The projector 2 is installed on the ceiling C, and projects and displays the projected image P1 on the screen SC. The screen SC is an example of a display surface. The projected image P1 is an example of an image.

The light curtain generation device 3 is installed on the ceiling C like the projector 2, and emits light (hereinafter referred to as “light curtain”) L in a flat infrared wavelength band. The light curtain L is used to detect the designated position P2 on the projected image P1 pointed to by the user with the indicator Q. The indicator Q is, for example, a user's finger, a stick, a pen, or the like. The light curtain L is not limited to flat light, but may have other shapes.

The light curtain generation device 3 adjusts the angle of the light curtain L with respect to the screen SC by changing the emission direction of the light curtain L to at least the ± θ direction shown in FIG. 2 under the control of the projector 2.

The image pickup unit 21 is, for example, a camera provided with a CCD (Charge Coupled Device), a CMOS (Complementary Metal Oxide Semiconductor), or the like, which is an image pickup element that converts light focused by an optical system such as a lens into an electric signal. .. The image pickup unit 21 is arranged at a position where the reflected light of the light curtain L can be imaged. An infrared filter for receiving the reflected light of the light curtain L is attached to the image pickup unit 21.

The image pickup unit 21 captures the projected image P1 on the screen SC to generate an captured image, and outputs the captured image to the projector 2. The captured image shows the reflected light of the light curtain L reflected by the indicator Q and the reflected light of the light curtain L reflected by the screen SC while adjusting the angle of the light curtain L with respect to the screen SC. Ru.

The projector 2 detects the reflection position of the light curtain L using the captured image. The projector 2 has a normal use mode and an angle adjustment mode of the light curtain L.
In the normal use mode, the projector 2 displays a cursor or the like at the reflection position (instruction position P2) of the light curtain L by the indicator Q.
In the angle adjustment mode of the light curtain L, the projector 2 controls the light curtain generation device 3 based on the reflection position of the light curtain L by the screen SC to adjust the angle of the light curtain L with respect to the screen SC. Hereinafter, the reflection position of the light curtain L by the screen SC is also simply referred to as “reflection position E”.

FIG. 3 is a diagram showing a projector 2 and a light curtain generator 3.
In addition to the image pickup unit 21, the projector 2 includes an input receiving unit 22, an image receiving unit 23, a storage unit 24, a control unit 25, a liquid crystal panel driving unit 26, and a projection unit 27. The light curtain generation device 3 includes a laser light source unit 31 that emits the light curtain L, and a changing unit 32 that changes the angle of the light curtain L with respect to the screen SC.

The input receiving unit 22 is, for example, various operation buttons, operation keys, a touch panel, or the like for receiving input from the user. The input receiving unit 22 may be a remote controller or the like that wirelessly or wiredly transmits information representing the input received from the user. In that case, the projector 2 includes a receiving unit that receives the information transmitted by the remote controller. The remote controller is provided with various operation buttons, operation keys, a touch panel, etc. for receiving input from the user.

The image receiving unit 23 receives an image signal indicating an image via an image input terminal or the like, and outputs the image signal to the control unit 25.

The storage unit 24 is a computer-readable recording medium, and is configured to include, for example, a RAM (Random Access Memory) and a ROM (Read Only Memory). The storage unit 24 may be configured to include an HDD (Hard Disk Drive), an SSD (Solid State Drive), or the like. The storage unit 24 stores various information, programs, and the like processed by the projector 2.

The control unit 25 is a computer such as a CPU (Central Processing Unit). The control unit 25 has an image processing unit 25a that processes an image signal by reading and executing a program stored in the storage unit 24, a position detection unit 25b that detects a reflection position of the light curtain L, and a light curtain generation device. A change control unit 25c that controls 3 is realized. All or part of the image processing unit 25a, the position detection unit 25b, and the change control unit 25c may be configured by hardware such as an FPGA (Field Programmable Gate Array) (not shown).
For example, the control unit 25 switches the mode of the projector 2 to either a normal use mode or an angle adjustment mode of the light curtain L according to the input of the user received from the input receiving unit 22.

The image processing unit 25a converts the image signal received from the image receiving unit 23 into image information representing the gradation of each pixel of the liquid crystal panel 27a included in the projection unit 27 for each RGB (Red, Green, Blue).

The liquid crystal panel drive unit 26 applies a drive voltage according to the image information input from the image processing unit 25a to each pixel of the liquid crystal panel 27a included in the projection unit 27.

The projection unit 27 is an example of a display unit. The projection unit 27 projects and displays the projection image P1 on the screen SC. The screen SC is not included in the display unit. The projection unit 27 includes a light source (not shown) and a reflector (not shown) that reflects the light emitted by the light source toward the liquid crystal panel 27a. The liquid crystal panel 27a is an example of an optical modulation device. Each pixel of the liquid crystal panel 27a modulates the light reflected by the reflector according to the drive voltage applied from the liquid crystal panel drive unit 26 to generate light representing an image corresponding to the image information. Then, the projection unit 27 projects the image light generated by the liquid crystal panel 27a onto the screen SC as a projection image P1 through a projection lens (not shown). The light source is, for example, a discharge type light source lamp composed of an ultrahigh pressure mercury lamp, a metal halide lamp, or the like, but the light source is not limited to the lamp, and an LED (Light Emitting Diode) light source, a laser light source, or the like may be used.

The position detection unit 25b detects the reflected position of the light curtain L based on the captured image obtained by capturing the reflected light of the light curtain L by the indicator Q and the reflected light of the light curtain L by the screen SC.

The change control unit 25c controls the change unit 32 based on the detection result of the position detection unit 25b to adjust the angle of the light curtain L with respect to the screen SC. In the present embodiment, the change control unit 25c controls the change control unit 32 so that the reflection position E of the light curtain L on the screen SC becomes the target position D (see FIG. 1).

The target position D is located in the region R on the opposite side of the light curtain generator 3 with the projected image P1 displayed on the screen SC. In the present embodiment, the target position D is a position in the region R in the vicinity of the projected image P1 (for example, the distance from the projected image P1 is 1 mm to 10 mm). The distance between the target position D and the projected image P1 is not limited to 1 mm to 10 mm and can be changed as appropriate. Hereinafter, the portion of the projected image P1 in contact with the region R is referred to as “lower end L1”. Further, the portion of the projected image P1 facing the lower end L1 is referred to as "upper end L2".

The change control unit 25c controls the change unit 32 by using the control signal S for controlling the rotation of the motor 32d and the motor 32e (see FIG. 3) included in the change unit 32. The control signal S indicates the rotation speed and the rotation direction of the motor 32d, and the rotation speed and the rotation direction of the motor 32e.

The laser light source unit 31 is, for example, a unit in which an optical system member such as a collimator lens or a Powell lens is attached to one or a plurality of LDs (Laser Diodes), and emits a light curtain L. The laser light source unit 31 is an example of an injection unit. The injection unit is not limited to the laser light source unit 31, and can be appropriately changed, and may be, for example, an LED.

The changing unit 32 includes a motor control unit 32a, motor drivers 32b and 32c, motors 32d and 32e, and adjusting mechanisms 32f and 32g. The motors 32d and 32e are stepping motors.
The motor control unit 32a controls the motor driver 32b and the motor driver 32c according to the control signal S from the change control unit 25c to rotate the motor 32d and the motor 32e. The motors 32d and 32e are examples of the drive unit, and the rotation of the motor 32d and the motor 32e is an example of driving the drive unit.

The adjusting mechanism 32f changes the angle of the light curtain L with respect to the screen SC by rotating the laser light source unit 31 about the rotation axis A shown in FIG. 4 according to the rotation of the motor 32d. When the laser light source unit 31 rotates about the rotation axis A, the direction of the light curtain L is changed to the ± θ direction shown in FIG. Here, the + θ direction is the direction in which the light curtain L is away from the screen SC, and the −θ direction is the direction in which the light curtain L is closer to the screen SC.

The adjusting mechanism 32g changes the angle of the light curtain L with respect to the screen SC by rotating the laser light source unit 31 about the rotation axis B shown in FIG. 4 in accordance with the rotation of the motor 32e. The rotation axis B is set so as to intersect the rotation axis A, for example, to be orthogonal to each other.

Next, the operation will be described.
FIG. 5 is a flowchart for explaining the operation of the light curtain L in the angle adjustment mode. Hereinafter, the position when the light curtain L moves most in the + θ direction is referred to as the “maximum position in the θ direction”, and the position when the light curtain L moves most in the −θ direction is referred to as the “minimum position in the θ direction”. Further, moving the light curtain L in the + θ direction is also referred to as “raising the light curtain L”, and moving the light curtain L in the −θ direction is also referred to as “lowering the light curtain L”.

When the projector 2 enters the angle adjustment mode of the light curtain L, the change control unit 25c first outputs a control signal S for rotating the motor 32d so that the light curtain L moves to the maximum position in the θ direction to the motor control unit 32a. do. The motor control unit 32a controls the motor driver 32b according to this control signal S to move the light curtain L to the maximum position in the θ direction (step S101). FIG. 6 is a diagram showing a state in which the light curtain L is located at the maximum position in the θ direction.

Subsequently, the change control unit 25c outputs a control signal S for rotating the motor 32d so that the light curtain L is lowered to the motor control unit 32a. The motor control unit 32a starts lowering the light curtain L according to the control signal S (step S102). Further, the change control unit 25c starts causing the image pickup unit 21 to repeatedly perform imaging of the screen SC (step S103).

When the light curtain L is lowered to irradiate the screen SC, the light curtain L is reflected (diffusely reflected) by the screen SC. Therefore, a part of the reflected light of the light curtain L by the screen SC is imaged by the image pickup unit 21.

Here, the farther the reflection position E of the light curtain L is from the image pickup unit 21, the weaker the reflected light of the light curtain L received by the image pickup unit 21. Further, the intensity of the reflected light of the light curtain L varies depending on the reflection characteristics of the screen SC. Therefore, when the reflection position E is located near the lower end L1 or in the region R, the reflected light of the light curtain L may not be displayed in the captured image.

Further, as shown in FIG. 7, when the convex portion (for example, the frame) H is provided in the region R, the light curtain L once irradiates the convex portion H in the situation where the light curtain L is lowered. Later, the screen SC will be irradiated.
The incident angle of the light curtain L is different between the surface I on the light curtain generator 3 side of the convex portion H and the screen SC, and the reflected light of the light curtain L on the convex portion H (plane I) is the screen SC. The probability of being incident on the image pickup unit 21 is higher than that of the reflected light of the light curtain L. Therefore, first, an captured image in which the reflected light at the convex portion H is displayed is generated, then an captured image in which the reflected light in the vicinity of the region R and the lower end L1 is not displayed is generated, and then from the lower end L1. However, there may be a situation where an image captured by displaying the reflected light on the screen SC on the upper end L2 side is generated.

The position detection unit 25b continues to detect the reflection position E based on the captured image repeatedly generated by the image pickup unit 21 while the light curtain L is lowered (step S104). The position detection unit 25b outputs the detection result of the reflection position E to the change control unit 25c.

Based on the detection result of the reflection position E, the change control unit 25c determines whether or not a situation has occurred in which the reflection position E matches the target position D (hereinafter referred to as “matching situation”) while the light curtain L is lowered. Is determined (step S105). The change control unit 25c has previously grasped the target position D, the position of the projected image P1, and the position of the area R.
For example, the projection unit 27 projects an image of a predetermined pattern (for example, an image whose entire surface is white) onto the screen SC in advance. The image pickup unit 21 captures an image of the pattern projected on the screen SC. The change control unit 25c acquires the image pickup result of the image pickup unit 21 via the position detection unit 25b. The change control unit 25c analyzes the image pickup result of the image pickup unit 21 and grasps the position of the projected image P1 corresponding to the white region. Subsequently, the change control unit 25c grasps the position of the region R on the side opposite to the light curtain generation device 3 with the projection region P1 interposed therebetween. Subsequently, the change control unit 25c grasps the position of the region R at a position where the distance from the projected image P1 is 5 mm as the target position D.
Further, the input receiving unit 22 receives the input regarding the target position D, the position of the projected image P1 and the position of the area R from the user in advance, and the change control unit 25c responds to the input received by the input receiving unit 22. The target position D, the position of the projected image P1, and the position of the region R may be grasped.

When a matching situation occurs (step S105: YES), the change control unit 25c outputs a control signal S for rotating the motor 32d and the motor 32e so that the reflection position E becomes the target position D to the motor control unit 32a. The motor control unit 32a controls the motor driver 32b and the motor driver 32c according to the control signal S to move the reflection position E to the target position D (step S106).
The change control unit 25c may execute step S106 by stopping the rotation of the motor 32d and the motor 32e when a matching situation occurs while the light curtain L is lowered.

On the other hand, for example, as shown in FIG. 8, when the reflection position E (hereinafter referred to as “first position E1”) detected first after the light curtain L starts to fall is on the projected image P1, the change control unit 25c Determines that no match situation has occurred (step S105: NO). FIG. 8 is a diagram showing an example of the captured image U1 when the first position E1 is on the projected image P1.

When the matching situation does not occur, the change control unit 25c outputs a control signal S for rotating the motor 32d so that the light curtain L moves to the minimum position in the θ direction to the motor control unit 32a. The motor control unit 32a controls the motor driver 32b according to the control signal S to move the light curtain L to the minimum position in the θ direction (step S107). FIG. 9 is a diagram showing an example of the captured image U2 when the light curtain L is located at the minimum position in the θ direction.

Subsequently, in the change control unit 25c, for example, when the line formed by the reflection position E is not parallel to the lower end L1 as shown in FIG. 9 (step S108: NO), the line formed by the reflection position E is the lower end L1. A control signal S for rotating the motor 32e so as to be parallel is output to the motor control unit 32a. The motor control unit 32a controls the motor driver 32c according to this control signal S to make the line formed by the reflection position E parallel to the lower end L1 (step S109). FIG. 10 is a diagram showing an example of the captured image U3 when the line formed by the reflection position E is parallel to the lower end L1. If the line formed by the reflection position E is parallel to the lower end L1 at the end of step S107 (step S108: YES), step S109 is skipped.

Subsequently, the change control unit 25c outputs a control signal S for rotating the motor 32d so that the light curtain L rises to the motor control unit 32a. The motor control unit 32a controls the motor driver 32b according to the control signal S to raise the light curtain L (step S110). The control signal S used here is a control signal in which the movement amount M of the reflection position E when the light curtain L is raised is equal to or less than the movement amount to the reflection position E (first position E1) shown in FIG. .. Therefore, the reflection position E moved by the control signal S is displayed in the captured image.

Subsequently, the change control unit 25c measures the relationship between the rotation speed G of the motor 32d used in step S110 and the movement amount M of the reflection position E accompanying the rotation speed G (step S111). For example, the change control unit 25c specifies the rotation speed G from the control signal S used in step S110, and the movement amount M from the detection results of the position detection units 25b before and after step S111.

As an example of the relationship between the rotation speed G and the movement amount M, for example, when the movement amount M of the reflection position E is half the distance from the upper end L2 to the lower end L1 when the motor 32d rotates 32 times, the rotation speed G is "32 rotations" and the movement amount M becomes "half the distance from the upper end L2 to the lower end L1". The relationship between the rotation speed G and the movement amount M is not limited to the above-mentioned relationship. Further, the rotation speed is not limited to an integer, and may be indicated by, for example, a fraction, or may be indicated by the number of steps of the motor 32d. The rotation speed of the motor 32d is an example of the driving amount of the driving unit.

Subsequently, the change control unit 25c determines the target rotation speed T for moving the reflection position E to the target position D based on the relationship between the rotation speed G and the movement amount M (step S112). The target rotation speed T is an example of a target drive amount.
Here, assuming that the distance from the current reflection position E to the target position D is the distance F, the change control unit 25c sets, for example, the target rotation speed T.
It is determined using the calculation formula of the target rotation speed T = (distance F × rotation speed G) / (movement amount M).
The change control unit 25c may calculate the target rotation speed using a calculation formula different from the above-mentioned calculation formula. For example, the change control unit 25c
The target rotation speed T may be calculated using the calculation formula of the target rotation speed T = coefficient J × (distance F × rotation speed G) / (movement amount M). The coefficient J is a constant larger than 1.

Subsequently, the change control unit 25c outputs a control signal S for rotating the motor 32d by the target rotation speed T to the motor control unit 32a. The motor control unit 32a controls the motor driver 32b according to the control signal S to rotate the motor 32d by the target rotation speed T (step S113). As a result, the reflection position E moves to the target position D. FIG. 11 is a diagram showing a captured image U4 when the reflection position E is located at the target position D.

Here, for example, when the convex portion H (see FIG. 7) is provided in the vicinity of the target position D, the position detecting unit 25b can detect the reflection position E even if the indicator Q does not exist. There is sex.
Therefore, when the position detection unit 25b detects the reflection position E when the step S113 is completed (step S114: YES), the change control unit 25c raises the light curtain L until the reflection position E is not detected. The control signal S for rotating the motor 32d is output to the motor control unit 32a. The motor control unit 32a controls the motor driver 32b according to this control signal S to raise the light curtain L until the reflection position E is no longer detected (step S115). If the position detection unit 25b has not detected the reflection position E when step S113 is completed, step S115 is skipped.

According to the present embodiment, the angle of the light curtain L with respect to the screen SC is changed based on the reflection position E of the light curtain L. Therefore, the complexity of the adjustment work can be reduced as compared with the case where the user arranges the jig on the screen SC and manually adjusts the direction of the light curtain L.

<Modification example>
The present invention is not limited to the above-described embodiment, and for example, various modifications as described below are possible. In addition, one or more variants arbitrarily selected from the following modifications can be combined as appropriate.

<Modification 1>
When the change control unit 25c controls the change unit 32 but the position detection unit 25b does not detect the target position D as the reflection position E (when no matching situation occurs), the change control unit 25c controls the laser light source unit 31 to control the light curtain L. The amount of light of may be larger than the amount of light at that time. For example, when the match condition does not occur (step S105: NO), the change control unit 25c increases the light amount of the light curtain L to be larger than the light amount at that time, and then returns the process to step S101.
According to the first modification, when the position detection unit 25b cannot detect the target position D as the reflection position E because the reflected light is weak, the light amount of the light curtain L can be made larger than the light amount at that time. Therefore, the reflected light can be strengthened, and the reflected position E can be easily detected.

<Modification 2>
If the position detection unit 25b does not detect the target position D as the reflection position E even if the change control unit 25c controls the change control unit 32, the sensitivity of the image pickup unit 21 may be higher than the sensitivity at that time. For example, when the match condition does not occur (step S105: NO), the change control unit 25c increases the sensitivity of the image pickup unit 21 by making the exposure time (light receiving time) of the image pickup unit 21 longer than the exposure time at that time. Higher than the sensitivity of. After that, the change control unit 25c returns the process to step S101.
According to the second modification, if the position detection unit 25b cannot detect the target position D as the reflection position E because the reflected light is weak, the sensitivity of the image pickup unit 21 can be increased. Therefore, the reflection position is easily displayed on the captured image, and the reflection position E is easily detected.

<Modification 3>
Step S109 may be executed after completing step S113.

<Modification example 4>
As shown in FIG. 12, the change control unit 25c may directly control the motor drivers 32b and 32c.

<Modification 5>
The projector 2, the light curtain generator 3, and the image pickup unit 21 may be composed of hardware in which two or more are integrated.

<Modification 6>
The display surface is not limited to the screen SC and can be changed as appropriate. For example, the display surface may be the plane of an object such as a wall or the top surface of a table.

<Modification 7>
The projector 2 may be installed on a table, a wall, or the like instead of being installed on the ceiling C. Further, the position where the light curtain generation device 3 is installed is not limited to the upper part of the screen SC, but may be the lower part of the screen SC, the left or right end of the screen SC, or the like.

<Modification 8>
The wavelength band of the light curtain L may be a wavelength band such as visible light.

<Modification 9>
The drive unit is not limited to the motor, and various actuators can be used as the drive unit.

<Modification 10>
The liquid crystal panel 27a used as the optical modulation device is configured by using, for example, three transmissive or reflective liquid crystal panels. Further, the optical modulation device has a configuration such as a method in which one liquid crystal panel and a color wheel are combined, a method in which three digital mirror devices (DMD) are used, and a method in which one digital mirror device and a color wheel are combined. May be. In addition to the liquid crystal panel and DMD, a configuration capable of modulating the light emitted by the light source can be adopted as the optical modulation device.

<Modification 11>
A projector was used as the display device, but the display device is not limited to the projector and can be changed as appropriate. For example, the display device may be a direct-view type display (liquid crystal display, organic EL (Electro Luminescence) display, plasma display, CRT (cathode ray tube) display, etc.).

<Modification 12>
In the above-described embodiment, the change control unit 25c moves the light curtain L to the maximum position in the θ direction (step S101), then moves the light curtain L in the lowering direction (step S102), and the image pickup unit 21 repeatedly generates the light curtain L. The position detection unit 25b continues to detect the reflection position E based on the captured image (step S104), and the change control unit 25c matches the reflection position E with the target position D while the light curtain L is lowered. It was determined whether or not it occurred (step S105). Instead, the light curtain L is moved to the minimum position in the θ direction in step S101, and then the position detection unit 25b continues to detect the reflection position E in step S104 while moving the light curtain L in the direction of raising the light curtain L in step S102. Then, in step S105, it may be determined whether or not a situation occurs in which the reflection position E coincides with the target position D.

1 ... Image display device, 2 ... Projector, 21 ... Image pickup unit, 22 ... Input receiving unit, 23 ... Image receiving unit, 24 ... Storage unit, 25 ... Control unit, 25a ... Image processing unit, 25b ... Position detection unit, 25c ... change control unit, 26 ... liquid crystal panel drive unit, 27 ... projection unit, 27a ... liquid crystal panel, 3 ... light curtain generator, 31 ... laser light source unit, 32 ... change unit, 32a ... motor control unit, 32b and 32c ... Motor driver, 32d and 32e ... motor, 32f and 32g ... adjustment mechanism, SC ... screen, L ... light curtain, P1 ... projection image.

Claims (4)

A display unit that displays an image on the display surface,
The injection part that emits light and
A changing part that changes the angle of the light emitted from the emitting part with respect to the display surface, and a changing part.
A position detection unit that detects the reflection position where the emitted light from the injection unit is reflected, and
Including a change control unit that controls the change unit,
The changing unit includes a driving unit and an adjusting mechanism that changes the angle according to the driving of the driving unit.
The change control unit is an image display device that controls the drive of the drive unit based on the detection result of the position detection unit.
When the change control unit does not detect the target position on the side opposite to the injection unit as the reflection position with the image on the display surface sandwiched between the position detection unit even if the drive of the drive unit is controlled. Determines the target drive amount for moving the reflection position to the target position based on the relationship between the drive amount of the drive unit and the movement amount of the reflection position, and drives the drive unit by the target drive amount. An image display device characterized by this . If the position detection unit does not detect the target position as the reflection position even if the drive unit is controlled, the change control unit detects the position detection unit when the drive unit is driven. The image display device according to claim 1 , wherein the relationship is measured based on the result, and the target drive amount is determined based on the measured relationship. When the position detection unit detects the reflection position when the drive unit is driven by the target drive amount, the change control unit drives the drive unit until the position detection unit does not detect the reflection position. The image display device according to claim 1 or 2 , wherein the drive of the unit is controlled. It has a display unit that displays an image on the display surface, an emission unit that emits light, and a change unit that changes the angle of the light emitted from the emission unit with respect to the display surface, and the change unit is driven. A method for controlling an image display device, which includes a unit and an adjustment mechanism that changes the angle according to the drive of the drive unit .
The step of detecting the reflection position where the emitted light of the ejection portion is reflected, and
A step of controlling the drive of the drive unit based on the detection result of the reflection position, and
If the target position on the display surface opposite to the injection unit is not detected as the reflection position even if the drive of the drive unit is controlled, the drive amount of the drive unit and the reflection are not detected. A step of determining a target drive amount for moving the reflection position to the target position based on the relationship with the position movement amount, and a step of determining the target drive amount.
A control method for an image display device, comprising : a step of driving the driving unit by the target driving amount .

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