JP2024044350A - Control device, image projection system, control method, and program - Google Patents

Abstract

[Problem] To provide a control device capable of performing suitable focus adjustment for images projected from a plurality of image projection devices. [Solution] A control device (A) that controls a first image projection device (1001) that projects a first image (SC1) and a second image projection device (1002) that projects a second image (SC2) has a comparison unit (A1) that compares a first shift amount of a first projection optical system of the first image projection device with a second shift amount of a second projection optical system of the second image projection device, and a focus control unit (A2) that controls the focus adjustment of each of the first image projection device and the second image projection device, and the focus control unit causes the control of the focus adjustment of each of the first image projection device and the second image projection device to differ from each other based on the comparison result of the comparison unit between the first shift amount and the second shift amount. [Selected Figure] Figure 2

Description

The present invention relates to a control device, an image projection system, a control method, and a program.

Conventionally, image projection systems (multi-projection systems) using multiple image projection devices (projectors) are known. In such image projection systems, the installation location of the image projection device is restricted depending on the exhibition environment, and it is not always possible to install the image projection device in front of the screen. In this case, it is necessary to adjust the projected image to the desired position by adjusting the lens shift amount (image height) of the projection lens (projection optical system). Depending on the installation environment, the lens shift amount may differ for each image projection device. In addition, the depth of field when the lens shift amount is large, i.e., at a position where the image height is high, is shallower than the depth of field when the lens shift amount is small, i.e., at a position around the optical axis. Therefore, a projected image from an image projection device with a large lens shift amount may be more likely to deteriorate than a projected image from an image projection device with a small lens shift amount.

Patent Document 1 discloses a projector that projects a test pattern, captures the image with an imaging unit, and automatically adjusts the focus position. Patent Document 2 discloses a projector in which a projection lens is shifted along a structure having a curved surface shape for correcting field curvature according to the image height.

Patent No. 3925513 Japanese Patent Application Publication No. 2006-18247

However, Patent Document 1 assumes the installation of a single projector, and does not allow for suitable adjustment of images projected by multiple projectors. The projector disclosed in Patent Document 2 requires the structure to be created with high precision, and may not be able to properly correct the image if there are individual differences in the amount of field curvature for each projection lens.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a control device that can suitably perform focus adjustment on images projected from a plurality of image projection devices.

A control device according to one aspect of the present invention is a control device that controls a first image projection device that projects a first image and a second image projection device that projects a second image, the first image projection device a comparison unit that compares a first shift amount of a first projection optical system of the second image projection device with a second shift amount of a second projection optical system of the second image projection device; a focus control unit that performs control regarding focus adjustment of each of the devices, and the first image and the second image are arranged such that a partial area of the first image and a partial area of the second image overlap each other. The first shift amount is a shift amount in a direction parallel to the optical axis of the first projection optical system from a first reference position of the first projection optical system, The second shift amount is a shift amount in a direction parallel to the optical axis of the second projection optical system from the second reference position of the second projection optical system, and the focus control section is configured to control the second shift amount by the comparison section. Based on a comparison result between the first shift amount and the second shift amount, control regarding the focus adjustment of the first image projection device and the second image projection device is made different from each other.

Other objects and features of the invention are explained in the following embodiments.

The present invention provides a control device that can perform optimal focus adjustments on images projected from multiple image projection devices.

FIG. 2 is a configuration diagram of an image projection device in each embodiment. FIG. 1 is a configuration diagram of an image projection system in a first embodiment. 3 is a flowchart showing the operation of the image projection system in the first embodiment. FIG. 11 is a configuration diagram of an image projection system according to a second embodiment. It is a flow chart showing operation of an image projection system in a 2nd embodiment. It is a block diagram of the image projection system in 3rd Embodiment. 13 is a flowchart showing the operation of an image projection system in a third embodiment. FIG. 13 is a configuration diagram of an image projection system according to a fourth embodiment.

The following describes in detail an embodiment of the present invention with reference to the drawings.

First, with reference to FIG. 1, a projector (image projection device) 100 in each embodiment will be described. FIG. 1 is a configuration diagram of a projector 100. The projector 100 is used as one image projection device that constitutes an image projection system in each embodiment described later.

A video signal provided from an external device such as a PC is first input to the video signal input unit 101. The video signal input unit 101 includes an AD conversion unit that converts analog signals such as VGA signals or Video signals into digital signals, and a receiver that converts digital signals such as HDMI (registered trademark) or DVI into a predetermined digital signal format. The digital video signal converted by the video signal input unit 101 is sent to the video signal processing unit 102. The video signal processing unit 102 is composed of a processor dedicated to video signal processing, and performs scaling processing to read the resolution of the input video signal and convert it into the resolution required for internal processing, menu display when buttons are operated, trapezoid correction (keystone correction), and other processing. The digital signal processed into a predetermined format by the video signal processing unit 102 is sent to the panel driving unit 103 and converted into a liquid crystal driving signal that drives the liquid crystal panel (light modulation unit) 109 described later.

The power supply unit 104 converts AC power input from the outside into DC power, and supplies power to the light source drive unit 105 or each part within the projector 100. The light source drive unit 105 is a drive circuit for lighting the light source unit 106, and controls the amount of light by turning on or off, or controlling power or current, according to a drive control signal from the CPU 113.

The light source unit 106 is composed of a lamp light source or a solid light source such as a laser or LED. When the light source unit 106 has a lamp light source, for example, an ultra-high pressure mercury lamp or a xenon lamp that emits white light is used. When the light source unit 106 has a laser light source, for example, a configuration is used in which white light is obtained by combining a monochromatic laser light with fluorescent light obtained by exciting a phosphor with the laser light. When the light source unit 106 has an LED light source, for example, a configuration is used in which LED light of each color R, G, and B is combined to obtain white light. The light emitted from the light source unit 106 is irradiated onto the illumination optical system 107.

The illumination optical system 107 homogenizes the light from the light source unit 106 by using multiple optical elements such as a fly-eye lens. The color separation optical system 108 separates the white light from the illumination optical system 107 into three colors, RGB. The liquid crystal panel 109 modulates each of the three separated colors according to a signal from the panel driving unit 103. The color synthesis optical system 110 combines the three colors, RGB, modulated by the three liquid crystal panels 109 into the same optical path. The lens shift unit 111 is an optical unit that holds the projection lens unit 112 so that it can move in an in-plane direction perpendicular to the optical axis. The lens shift unit 111 has a moving unit 111a having a moving member that moves the projection lens unit 112 independently in the vertical and horizontal directions, a lens shift adjustment unit 111b that drives each moving member, and a lens shift identification unit 111c that identifies the lens shift amount. The lens shift adjustment unit 111b has a motor and a gear unit (both not shown) that is connected to the motor and the moving unit 111a and transmits the rotation of the motor to the moving unit 111a after slowing it down to a desired speed. The lens shift identification unit 111c has a sensor that detects the amount of lens shift from the amount of movement of the moving unit 111a.

The projection lens unit 112 enlarges and projects the light emitted from the color synthesis optical system 110 onto the screen at a predetermined magnification. The projection lens unit 112 has a projection lens (projection optical system) 112a, a focus adjustment unit 112b that adjusts the focus position of the projection lens 112a, and a focus identification unit 112c that identifies the adjustment amount of the focus adjustment unit 112b. The focus adjustment unit 112b has a motor and a gear unit (both not shown) that is connected to a lens barrel that holds the motor and optical parts that move to adjust the focus, and transmits the rotation of the motor to the lens barrel by slowing it down to a desired speed. The focus identification unit 112c has a sensor for detecting the focus adjustment amount from the movement amount of the lens barrel (not shown). The sensor used for the lens shift identification unit 111c and the focus identification unit 112c is an encoder that converts the mechanical position change of a variable resistor into a digital signal, or a photointerrupter that detects the light blocking period of the light from the light emitting unit with a light receiving unit to detect the position.

The CPU 113 is a control unit composed of a microcomputer and performs overall control of the projector 100. For example, the CPU 113 controls the light source unit 106 by turning it on and off, the power supply to each light source, or the power supply to each circuit and the rotation of the cooling fan, using a control signal sent to the light source driving unit 105. The operation panel 114 is composed of buttons for turning the power on and off and for setting various menus. When the CPU 113 detects that a button on the operation panel 114 has been pressed, it determines which button on the operation panel 114 has been pressed and controls each unit required for that operation. The adjustment pattern generating unit 115 generates a predetermined pattern (adjustment pattern) that serves as a guide for adjustment when the user manually adjusts the focus of the projection lens unit 112.

Each embodiment will be described in detail below.
First Embodiment
First, an image projection system 200 according to a first embodiment of the present invention will be described with reference to Fig. 2. Fig. 2 is a configuration diagram of the image projection system 200. The image projection system 200 includes a projector (first image projection device) 1001, a projector (second image projection device) 1002, a control device A, and an imaging device C.

The projectors 1001 and 1002 are image projection devices having the same configuration as the above-described projector 100, but are given different symbols for convenience of explanation. The projector 1001 includes a lens shift identification section 111c1 and a focus adjustment section 112b1. Similarly, the projector 1002 includes a lens shift identification section 111c2 and a focus adjustment section 112b2. The lens shift identification section 111c1 and the lens shift identification section 111c2 have the same function, but are given different symbols for convenience of explanation. Furthermore, the focus adjustment section 112b1 and the focus adjustment section 112b2 have the same functions, but are given different symbols. Note that these points also apply to each embodiment described below.

Projector 1001 and projector 1002 respectively project a projection image (first image) SC1 and a projection image (second image) SC2, and perform multi-projection to display a multi-image M by superimposing a part of projection image SC1 and a part of projection image SC2. Multi-image M has a blending area (overlapping area) B where the projection images from projector 1001 and projector 1002 are superimposed. Note that blending area B is brighter than non-overlapping areas due to the superimposition of the projection images. In blending area B, dimming processing is applied to the overlapping area of the images for averaging. For example, processing is performed to gradually reduce the brightness from the start point to the end point of the overlap of the overlapping parts (overlapping areas) of each image.

As shown in FIG. 2, the lens shift amount (first shift amount) of the projection lens (first projection optical system) of the projector 1001 and the lens shift amount (first shift amount) of the projection lens (second projection optical system) of the projector 1002 are shown. 2 shift amounts) are different from each other. Here, the first shift amount is a shift amount in a direction parallel to the optical axis of the first projection optical system from the first reference position of the projector 1001. Similarly, the second shift amount is a shift amount from the second reference position of the projector 1002 in a direction parallel to the optical axis of the second projection optical system. Here, the first reference position is a position where the light emitted from the center of the liquid crystal panel (first light modulation unit) of the projector 1001 and the optical axis of the first projection optical system coincide with each other. Similarly, the second reference position is a position where the light emitted from the center of the liquid crystal panel (second light modulation unit) of the projector 1002 and the optical axis of the second projection optical system coincide with each other. FIG. 2 shows a state in which the lens shift amount in the projector 1001 is 0% in the vertical direction and 0% in the horizontal direction, and the lens shift amount in the projector 1002 is 0% in the vertical direction and 50% in the horizontal direction.

The control device A is a personal computer including a CPU such as a microcomputer, and includes a determination section (comparison section) A1 and a control section (focus control section) A2. The determination unit A1 communicates with the lens shift identification unit 111c1 and the lens shift identification unit 111c2, respectively, and determines the magnitude of the lens shift amount. That is, the determination unit A1 is a comparison unit that compares the first shift amount of the first projection optical system of the projector 1001 and the second shift amount of the second projection optical system of the projector 1002. Further, the determination unit A1 determines whether or not the focus of the projected images from the projector 1001 and the projector 1002 is suitable, based on the captured image acquired by the imaging device C. The control unit A2 calculates control parameters for each of the focus adjustment units 112b1 and 112b2 based on the information (determination result, comparison result) from the determination unit A1, and transmits the calculated parameters to the projectors 1001 and 1002, respectively. Perform focus control.

The imaging device C is a camera that is installed so that the imaging range includes a multi-image M, which will be described later. The imaging device C transmits the captured image to the determination unit A1.

Next, the operation of the image projection system 200 (autofocus (AF) adjustment operation) will be described with reference to FIG. 3. FIG. 3 is a flowchart showing the operation of the image projection system 200. Note that FIG. 3 describes a case where the first shift amount is smaller than the second shift amount, the first shift amount is the lens shift amount of projector 1001, and the second shift amount is the lens shift amount of projector 1002. However, this embodiment is not limited to this, and the first shift may be the lens shift amount of projector 1002, and the second shift amount may be the lens shift amount of projector 1001.

First, in step S101, under the control of the control device A, the image capture device C captures a multi-image M formed by the projected images SC1 and SC2 projected by the projectors 1001 and 1002, acquires the captured image, and transmits the captured image to the control device A. Next, in step S102, the control device A associates the captured image with the projectors 1001 and 1002 responsible for projecting the projected images SC1 and SC2. This association process may be performed as an internal process of the control device A by comparing the projected images from each projector with the captured image, or may be performed separately by the user using a dedicated application built into the control device A.

Subsequently, in step S103, the control unit A2 identifies a blend area (superimposed area) B between the projection image SC1 and the projection image SC2. This identification process may be performed as an internal process of the control device A based on the difference between the brightness of the blend area B and the brightness of the non-blend area, or may be performed separately using a dedicated application built into the control unit A2. This may be done in a form specified by the user.

Subsequently, in step S104, the determination unit A1 acquires the lens shift amount (first shift amount) of the projector 1001 from the lens shift identification unit 111c1. Similarly, the determination unit A1 acquires the lens shift amount (second shift amount) of the projector 1002 from the lens shift identification unit 111c2. Subsequently, in step S105, the determining unit A1 determines whether the shift amount is smaller than that of the projector projecting an adjacent image. That is, the determination unit A1 compares the lens shift amounts of two projectors 1001 and 1002 that project adjacent images.

If it is determined in step S105 that the lens shift amount is smaller than that of the projector projecting an adjacent image, the process advances to step S106. Here, since the lens shift amount of the projector 1001 is smaller than the lens shift amount of the projector 1002, the process advances to step S106 when controlling the focus adjustment of the projector 1001.

In step S106, the control unit A2 performs focus adjustment processing by setting the image area including the blend area B in the captured image of the projection image SC1 as a focus adjustment area (focus adjustment area FA1 in FIG. 2). Subsequently, in step S107, the control unit A2 calculates control parameters necessary for performing focus adjustment with reference to the focus adjustment area FA1, and transmits the desired parameters to the focus adjustment unit 112b1. Subsequently, in step S108, the control unit A2 acquires the captured image transmitted from the imaging device C. Subsequently, in step S109, if the control unit A2 determines that the focus position of the focus adjustment area FA1 in the projection image SC1 has become suitable (focus adjustment completed), it ends the focus adjustment operation of the projector 1001. On the other hand, if it is determined that the focus position of the focus adjustment area FA1 is not suitable (the focus adjustment is not completed), the process returns to step S106.

On the other hand, if it is determined in step S105 that the lens shift amount is greater than that of the projector projecting the adjacent image, the process proceeds to step S110. In this case, since the lens shift amount of projector 1002 is greater than the lens shift amount of projector 1001, the process proceeds to step S110 when controlling the focus adjustment of projector 1002.

In step S110, the control unit A2 performs focus adjustment processing by setting the image area excluding the blending area B as the focus adjustment area (focus adjustment area FA2 in FIG. 2). Then, in step S111, the control unit A2 calculates the control parameters required for focus adjustment by referring to the focus adjustment area FA2, and transmits the desired parameters to the focus adjustment unit 112b2. Then, in step S112, the control unit A2 acquires the captured image transmitted from the imaging device C. Then, in step S113, if the control unit A2 determines that the focus position of the focus adjustment area FA2 in the projection image SC2 has become suitable (focus adjustment has ended), it ends the focus adjustment operation of the projector 1002. On the other hand, if the control unit A2 determines that the focus position of the focus adjustment area FA2 is not suitable (focus adjustment has not ended), it returns to step S110.

When the lens shift amounts of the projectors 1001 and 1002 are different from each other, the projected image projected by the projector with a large lens shift amount (for example, the projector 1002) suffers from optical resolution deterioration according to the image height (lens shift amount). big. At this time, by limiting the focus adjustment area of the projector 1002 to the focus adjustment area FA2 as described above, deterioration in resolution can be reduced compared to the case where adjustment is performed by referring to the entire area of the projected image.

On the other hand, for a projector with a small lens shift amount (e.g., projector 1001), the resolution degradation is small compared to projector 1002. Therefore, even if the focus adjustment area of projector 1001 is adjusted with reference to focus adjustment area FA1, i.e., projected image SC1, the degree of resolution degradation is limited.

Therefore, by projecting an image with focus adjustment over the entire projection image (focus adjustment area FA1) and an image with focus adjustment over a limited projection image area (focus adjustment area FA2), a multi-projection screen with little difference in resolution degradation and no sense of incongruity can be obtained.
Second Embodiment
Next, an image projection system 300 according to a second embodiment of the present invention will be described with reference to Fig. 4. Fig. 4 is a configuration diagram of the image projection system 300. Note that in this embodiment, the same functions or configurations as those in the first embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

The image projection system 300 is configured with a projector (first image projection device) 1001a, a projector (second image projection device) 1002a, a control device A, and an imaging device C. The projector 1001a is equipped with a lens shift identification unit 111c1 and an adjustment pattern generation unit 1151. Similarly, the projector 1002a is equipped with a lens shift identification unit 111c2 and an adjustment pattern generation unit 1152. Note that the adjustment pattern generation unit 1151 and the adjustment pattern generation unit 1152 have the same functions, but are given different reference numerals. The control unit A2 controls the adjustment pattern generation units 1151 and 1152 based on information from the determination unit A1 to generate patterns (adjustment patterns) that allow the user to suitably adjust the focus of the projection images from the projectors 1001a and 1002a.

Next, the operation (focus adjustment operation) of the image projection system 200 will be described with reference to FIG. 5. FIG. 3 is a flowchart showing the operation of the image projection system 200. Note that in FIG. 3, it is assumed that the first shift amount is smaller than the second shift amount, the first shift amount is the lens shift amount of the projector 1001, and the second shift amount is the lens shift amount of the projector 1002. However, this embodiment is not limited to this, and the first shift may be the lens shift amount of the projector 1002, and the second shift amount may be the lens shift amount of the projector 1001.

Next, the operation of the image projection system 300 (manual focus (MF) adjustment operation) will be described with reference to FIG. 5. FIG. 5 is a flowchart showing the operation of the image projection system 300. Note that FIG. 5 describes a case where the first shift amount is smaller than the second shift amount, the first shift amount is the lens shift amount of projector 1001a, and the second shift amount is the lens shift amount of projector 1002a. However, this embodiment is not limited to this, and the first shift may be the lens shift amount of projector 1002a, and the second shift amount may be the lens shift amount of projector 1001a.

Steps S201 to S206 and S209 in FIG. 5 are the same as steps S101 to S106 and S110 in FIG. 3, respectively, so a description thereof will be omitted.

In step S207, the control unit A2 refers to the focus adjustment area FA1 and generates and displays an adjustment pattern PT1 for adjusting the focus adjustment unit 112b, and transmits a signal to the adjustment pattern generation unit 1141. The user adjusts the focus adjustment unit 112b1 so that the focus of the focus adjustment area FA1 becomes suitable while referring to the adjustment pattern PT1. Next, in step S208, if the control unit A2 determines that the focus position of the focus adjustment area FA1 in the projection image SC1 has become suitable (a focus adjustment end operation has been performed), it ends the focus adjustment operation of the projector 1001a. On the other hand, if it determines that the focus position of the focus adjustment area FA1 is not suitable (no focus adjustment end operation has been performed), it returns to step S206.

In step S210, the control unit A2 transmits a signal to the adjustment pattern generation unit 1152 to generate and display an adjustment pattern PT2 for adjusting the focus adjustment unit 112b with reference to the focus adjustment area FA2. The user adjusts the focus adjustment unit 112b2 so that the focus of the focus adjustment area FA2 becomes suitable while referring to the adjustment pattern PT2. Subsequently, in step S211, if the control unit A2 determines that the focus position of the focus adjustment area FA2 in the projection image SC2 has become suitable (there is an operation to end the focus adjustment), the control unit A2 ends the focus adjustment operation of the projector 1002a. do. On the other hand, if it is determined that the focus position of the focus adjustment area FA2 is not suitable (there is no focus adjustment end operation), the process returns to step S209.

The adjustment patterns PT1 and PT2 shown in FIG. 4 each have a cross shape, and are displayed at five locations, namely the center, upper right, lower right, upper left, and lower left of the focus adjustment areas FA1 and FA2. The shape of the pattern and the display location are not limited to this. For example, other adjustment patterns may be displayed, such as a grid pattern in which vertical and horizontal lines are displayed over the entire projected image, a pattern in which predetermined text is continuously displayed, or a pattern in which predetermined photographs are displayed.

When the lens shift amounts of the projectors 1001a and 1002a are different from each other, the projected image projected by the projector with a larger lens shift amount (for example, the projector 1002a) suffers from optical resolution deterioration according to the image height (lens shift amount). big. At this time, as described above, by limiting the area in which the user adjusts the focus of the projector 1002a to the focus adjustment area FA2, deterioration in resolution can be reduced compared to when adjusting by referring to the entire area of the projected image. Can be done.

On the other hand, for a projector with a small lens shift amount (e.g., projector 1001a), the resolution degradation is small compared to projector 1002a. Therefore, even if the user adjusts the area for adjusting the focus of projector 1001a by referring to focus adjustment area FA1, i.e., projected image SC1, the degree of resolution degradation is limited.

Therefore, by projecting an image whose focus has been adjusted in the entire projection image area (focus adjustment area FA1) and an image whose focus has been adjusted in a limited projection image area (focus adjustment area FA2), the difference in resolution deterioration is small and the image can be multiplied without any discomfort. You can get a projection screen.
(Third embodiment)
Next, with reference to FIG. 6, an image projection system 400 according to a third embodiment of the present invention will be described. FIG. 6 is a configuration diagram of the image projection system 400. This embodiment relates to multi-projection using three projectors. Note that in this embodiment, the same functions or configurations as in the first embodiment are denoted by the same reference numerals, and detailed explanation thereof will be omitted.

The image projection system 400 is configured with a projector (first image projection device) 1001, a projector (second image projection device) 1002, a projector (third image projection device) 1003, a control device A, and an imaging device C. The projector 1003 has the same functions as the projectors 1001 and 1002, and includes a lens shift identification unit 111c3 and a focus adjustment unit 112b3.

Projectors 1001, 1002, and 1003 perform multi-projection by projecting projection images SC1, SC2, and SC3, respectively, and partially overlapping them to display a multi-image M. Multi-image M has a blending area (first overlapping area) B12 where projection images SC1 and SC2 are overlapped, and a blending area (second overlapping area) B23 where projection images SC2 and SC3 are overlapped. The lens shift amounts of projectors 1001, 1002, and 1003 are different from each other. Here, projector 1001 is 0% vertically and 0% horizontally, projector 1002 is 0% vertically and 50% horizontally, and projector 1003 is 0% vertically and 30% horizontally.

Next, the operation (autofocus (AF) adjustment operation) of the image projection system 400 will be described with reference to FIG. 7. FIG. 7 is a flowchart showing the operation of image projection system 400. Note that in FIG. 7, the description will be made assuming that the first shift amount is smaller than the second shift amount, and the third shift amount is smaller than the second shift amount. Further, a case will be described in which the first shift amount is the lens shift amount of the projector 1001, the second shift amount is the lens shift amount of the projector 1002, and the third shift amount is the lens shift amount of the projector 1003. However, this embodiment is not limited to this.
Note that in FIG. 7, steps S301, S302, and S306 to S314 are the same as steps S101, S102, and S105 to S113 in FIG. 3, respectively, so a description thereof will be omitted.

In step S303, the control unit A2 identifies a blend region (first superimposed region) B12 formed by the projectors 1001 and 1002 and a blend region (second superimposed region) B23 formed by the projectors 1002 and 1003, respectively. Subsequently, in step S304, the determination unit A1 obtains the lens shift amounts (first, second, and third shift amounts) of the projectors 1001, 1002, and 1003 from the lens shift identification units 111c1, 111c2, and 111c3, respectively. Subsequently, in step S305, the determining unit A1 determines whether a plurality of blend areas (superimposed areas) exist for each of the projection images SC1, SC2, and SC3 of the projectors 1001, 1002, and 1003. If it is determined that a plurality of blend regions do not exist, the control device A performs the same operations as in the first embodiment in steps S306 to S314. In this embodiment, only one blend area (blend area B12 or blend area B23) exists for the projected images SC1 and SC3 of the projectors 1001 and 1003, so the process advances to step S306.

On the other hand, if it is determined that multiple blending areas exist, the process proceeds to step S315. In this embodiment, two blending areas B12 and B23 exist for the projection image SC2 of the projector 1002, so the process proceeds to step S315. In step S315, the determination unit A1 determines the blending area to be determined from the multiple blending areas B12 and B23. In this embodiment, first, the blending area B12 is determined to be the object of determination.

Subsequently, in step S316, the determining unit A1 determines whether the shift amount is smaller than that of the projector projecting an adjacent image. That is, the determination unit A1 compares the lens shift amounts of two projectors 1001 and 1002 that project adjacent images. If it is determined in step S316 that the lens shift amount is smaller than that of the projector projecting an adjacent image, the process advances to step S317. Here, since the lens shift amount of the projector 1001 is smaller than the lens shift amount of the projector 1002, the process advances to step S317 when controlling the focus adjustment of the projector 1001. In this embodiment, the lens shift amount of the projector 1001 is smaller than the lens shift amount of the projector 1002. Therefore, in step S317, the control device A performs focus adjustment processing of the projector 1002 for the image area excluding the blend area on the blend area B12 side of the projection image SC2.

Subsequently, in step S319, the determination unit A1 determines whether all of the plurality of blend regions (adjacent locations) identified in step S303 have been determined. If it is determined that there is a blend area that has not been determined, the process returns to step S315 and another blend area that has not been determined is determined. Here, blend region B23 of the two blend regions is determined as the determination target. Note that the lens shift amount of the projector 1003 is smaller than the lens shift amount of the projector 1002. Therefore, in step S316, the control device A performs focus adjustment processing for the projector 1002 on the image area of the projected image SC2 excluding the blend area on the blend area B23 side.

If all blend areas (focus adjustment areas) are determined in step S319, the process advances to step S320. In step S320, the control unit A2 calculates control parameters necessary for performing focus adjustment with reference to the focus adjustment area FA2 in FIG. 6 for the projection image SC2, and transmits the desired parameters to the focus adjustment unit 112b2. do. Subsequently, in step S321, the control unit A2 acquires a captured image transmitted from the imaging device C.

Next, in step S322, if it is determined that the focus position of focus adjustment area FA2 in projected image SC2 has become suitable (focus adjustment completed), the focus adjustment operation of projector 1002 is terminated. On the other hand, if it is determined that the focus position of focus adjustment area FA2 is not suitable (focus adjustment not completed), the process returns to step S316. According to this embodiment, the same effect as in the first embodiment can be obtained even in multi-projection using three projectors.

When the lens shift amounts of projectors 1001, 1002, and 1003 are different from one another, the image projected by the projector with the larger lens shift amount (e.g., projector 1002) has a larger optical resolution degradation according to the image height (lens shift amount). In this case, by limiting the focus adjustment area of projector 1002 to focus adjustment area FA2 as described above, it is possible to reduce the degradation of resolution compared to the case where adjustment is made with reference to the entire area of the projected image.

On the other hand, for projectors with a small lens shift amount (e.g., projectors 1001 and 1003), the resolution degradation is small compared to projector 1002. Therefore, even if the focus adjustment areas of projectors 1001 and 1003 are adjusted with reference to focus adjustment areas FA1 and FA3, i.e., projected images SC1 and SC3, the degree of resolution degradation is limited.

Therefore, by projecting an image that has been focus-adjusted over the entire projection image area (focus adjustment areas FA1, FA3) and an image that has been focus-adjusted over a limited projection image area (focus adjustment area FA2), a multi-projection screen with little difference in resolution degradation and no sense of incongruity can be obtained.
Fourth Embodiment
Next, an image projection system 500 according to a fourth embodiment of the present invention will be described with reference to Fig. 8. Fig. 8 is a configuration diagram of the image projection system 500. This embodiment relates to multi-projection using four projectors. Note that in this embodiment, the same functions or configurations as those in the first embodiment are denoted by the same reference numerals, and detailed descriptions thereof will be omitted.

The image projection system 500 includes a projector (first image projection device) 1001, a projector (second image projection device) 1002, a projector (third image projection device) 1003, a projector (fourth image projection device) 1004, a control device A, and an imaging device C. The projector 1004 has the same functions as the projectors 1001 to 1003, and includes a lens shift identification unit 111c4 and a focus adjustment unit 112b4.

Projectors 1001 to 1004 project projection images SC1 to SC4, respectively, and perform multi-projection in which a portion of each projection image is superimposed to display a multi-image M. Multi-image M has blending area B12, blending area B24, blending area B13, and blending area B34.

The lens shift amounts of projectors 1001 to 1004 are different from each other. Here, projector 1001 is 50% vertically and 0% horizontally, projector 1002 is 50% vertically and 30% horizontally, projector 1003 is -60% vertically and 30% horizontally, and projector 1004 is -60% vertically and 30% horizontally.

In this embodiment, the lens shift amounts (first to fourth shift amounts) of each of the projectors 1001 to 1004 have the relationship of first shift amount < second shift amount < third shift amount = fourth shift amount. There is. For this reason, the focus adjustment process of the projector 1001 is performed on the blend areas B12 and B13 sides of the projected image SC1 from the projector 1001, with the image area including the blend area as the focus adjustment area. Focus adjustment processing of the projector 1002 is performed using the image area excluding the blend area on the blend area B12 side of the projected image SC2 from the projector 1002, and the image area including the blend area on the blend area B24 side as the focus adjustment area. Focus adjustment processing of the projector 1003 is performed using the image area excluding the blend area on the blend area B13 side of the projected image SC3 from the projector 1003, and the image area including the blend area on the blend area B34 side as the focus adjustment area. Focus adjustment processing of the projector 1004 is performed using the image area excluding the blend area on the blend area B24 side of the projected image SC4 from the projector 1004, and the image area including the blend area on the blend area B34 side as the focus adjustment area.

In this way, the projectors 1001 to 1004 refer to the focus adjustment areas FA1 to FA4 shown in FIG. 8 to calculate the control parameters necessary for focus adjustment, and transmit the desired parameters to the focus adjustment sections 112b1 to 112b4.
Other Embodiments
The present invention can also be realized by a process in which a program for implementing one or more of the functions of the above-described embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) that implements one or more of the functions.

According to each embodiment, it is possible to provide a control device, an image projection system, a control method, and a program that are capable of performing optimal focus adjustments on images projected from multiple image projection devices.

The disclosure of each embodiment includes the following configurations and methods:

(Configuration 1)
A control device that controls a first image projection device that projects a first image and a second image projection device that projects a second image,
a comparison unit that compares a first shift amount of a first projection optical system of the first image projection device and a second shift amount of a second projection optical system of the second image projection device;
a focus control unit that controls focus adjustment of each of the first image projection device and the second image projection device;
The first image and the second image are projected so as to have an overlapping area in which a partial area of the first image and a partial area of the second image overlap each other,
The first shift amount is a shift amount in a direction parallel to the optical axis of the first projection optical system from a first reference position of the first projection optical system,
The second shift amount is a shift amount in a direction parallel to the optical axis of the second projection optical system from a second reference position of the second projection optical system,
The focus control unit controls the focus adjustment of each of the first image projection device and the second image projection device based on a comparison result between the first shift amount and the second shift amount by the comparison unit. A control device characterized in that the two are different from each other.
(Configuration 2)
According to configuration 1, the control related to the focus adjustment is control related to setting a focus adjustment area used for adjusting the focus position of each of the first image and the second image in autofocus. control device.
(Configuration 3)
the first shift amount is smaller than the second shift amount,
The focus control section includes:
setting an image area of the first image including the overlapping area as the focus adjustment area for the first image projection device;
The control device according to configuration 2, wherein an image area of the second image excluding the superimposed area is set as the focus adjustment area for the second image projection device.
(Configuration 4)
The control according to configuration 1, wherein the control regarding the focus adjustment is a control regarding projection of an adjustment pattern used to manually adjust the focus position of each of the first image and the second image. Device.
(Configuration 5)
the first shift amount is smaller than the second shift amount,
The focus control section includes:
projecting the adjustment pattern onto an image area of the first image including the superimposed area on the first image projection device;
The control device according to configuration 4, wherein the control device projects the adjustment pattern onto an image area of the second image excluding the superimposed area, with respect to the second image projection device.
(Configuration 6)
The focus control unit controls the first image projection so as to reduce a difference in resolution deterioration between the first image projection device due to the first shift amount and the second image projection device due to the second shift amount. 6. The control device according to any one of configurations 1 to 5, wherein control regarding the focus adjustment of the device and the second image projection device is made different from each other.
(Configuration 7)
The first reference position is a position where the light emitted from the center of the first light modulation section of the first image projection device and the optical axis of the first projection optical system match each other,
The second reference position is a position where the light emitted from the center of the second light modulation section of the second image projection device and the optical axis of the second projection optical system coincide with each other. The control device according to any one of configurations 1 to 6.
(Configuration 8)
a first image projection device that projects a first image;
a second image projection device that projects a second image;
An image projection system comprising: the control device according to any one of configurations 1 to 7;
(Method 1)
A control method for controlling a first image projection device that projects a first image and a second image projection device that projects a second image, the method comprising:
a comparison step of comparing a first shift amount of the first projection optical system of the first image projection device and a second shift amount of the second projection optical system of the second image projection device;
a focus control step for controlling focus adjustment of each of the first image projection device and the second image projection device;
The first image and the second image are projected so as to have an overlapping area in which a partial area of the first image and a partial area of the second image overlap each other,
The first shift amount is a shift amount in a direction parallel to the optical axis of the first projection optical system from a first reference position of the first projection optical system,
The second shift amount is a shift amount in a direction parallel to the optical axis of the second projection optical system from a second reference position of the second projection optical system,
In the focus control step, control regarding the focus adjustment of each of the first image projection device and the second image projection device is performed based on the comparison result between the first shift amount and the second shift amount in the comparison step. A control method characterized by making the two different from each other.
(Configuration 9)
A program that causes a computer to execute the control method described in Method 1.

The above describes preferred embodiments of the present invention, but the present invention is not limited to these embodiments, and various modifications and variations are possible within the scope of the gist of the invention.

A Control device A1 Judgment section (comparison section)
A2 Control unit (focus control unit)
SC1 Projected image (first image)
SC2 Projected image (second image)
112a Projection lens (first projection optical system, second projection optical system)
1001 Projector (first image projection device)
1002 Projector (second image projection device)

Claims (10)

A control device that controls a first image projection device that projects a first image and a second image projection device that projects a second image,
a comparison unit that compares a first shift amount of a first projection optical system of the first image projection device with a second shift amount of a second projection optical system of the second image projection device;
a focus control unit that controls focus adjustment of each of the first image projection device and the second image projection device,
the first image and the second image are projected so as to have an overlapping region in which a partial region of the first image and a partial region of the second image overlap each other;
the first shift amount is a shift amount in a direction parallel to an optical axis of the first projection optical system from a first reference position of the first projection optical system,
the second shift amount is a shift amount in a direction parallel to an optical axis of the second projection optical system from a second reference position of the second projection optical system,
The control device is characterized in that the focus control unit causes the control regarding the focus adjustment of each of the first image projection device and the second image projection device to differ from each other based on the comparison result of the first shift amount and the second shift amount by the comparison unit. The control device according to claim 1, characterized in that the control related to the focus adjustment is control related to setting of a focus adjustment area used to adjust the focus positions of the first image and the second image in autofocus. the first shift amount is smaller than the second shift amount,
The focus control section includes:
setting an image area of the first image including the overlapping area as the focus adjustment area for the first image projection device;
3. The control device according to claim 2, wherein an image area of the second image excluding the overlapping area is set as the focus adjustment area for the second image projection apparatus. 2. The control related to the focus adjustment is control related to projection of an adjustment pattern used to manually adjust the focus position of each of the first image and the second image. Control device. the first shift amount is smaller than the second shift amount,
The focus control unit includes:
projecting the adjustment pattern onto an image area of the first image including the overlap area with respect to the first image projection device;
The control device according to claim 4 , wherein the second image projection device projects the adjustment pattern onto an image area of the second image excluding the overlap area. The control device according to claim 1, characterized in that the focus control unit controls the focus adjustment of the first image projection device and the second image projection device differently from each other so as to reduce the difference in degradation of the resolution of the first image projection device due to the first shift amount and the second image projection device due to the second shift amount. The first reference position is a position where the light emitted from the center of the first light modulation section of the first image projection device and the optical axis of the first projection optical system coincide with each other,
The second reference position is characterized in that the light emitted from the center of the second light modulation section of the second image projection device and the optical axis of the second projection optical system coincide with each other. The control device according to claim 1. a first image projection device that projects a first image;
a second image projection device that projects a second image;
An image projection system comprising: the control device according to claim 1 . 1. A control method for controlling a first image projection device that projects a first image and a second image projection device that projects a second image, comprising:
a comparing step of comparing a first shift amount of a first projection optical system of the first image projection device with a second shift amount of a second projection optical system of the second image projection device;
a focus control step of controlling focus adjustment of each of the first image projection device and the second image projection device,
the first image and the second image are projected so as to have an overlapping region in which a partial region of the first image and a partial region of the second image overlap each other;
the first shift amount is a shift amount in a direction parallel to an optical axis of the first projection optical system from a first reference position of the first projection optical system,
the second shift amount is a shift amount in a direction parallel to an optical axis of the second projection optical system from a second reference position of the second projection optical system,
A control method characterized in that, in the focus control step, the control regarding the focus adjustment of each of the first image projection device and the second image projection device is made different from each other based on the comparison result between the first shift amount and the second shift amount in the comparison step. A program that causes a computer to execute the control method according to claim 9.