JP6750269B2 - Projector and control method - Google Patents

Description

The present invention relates to a projector that performs processing according to the position of a pointer on a projection surface.

A technique is known in which detection light such as laser light is emitted along the projection surface and the position of the indicator on the projection surface is detected by the detection light reflected by the indicator (for example, Patent Document 1).

JP, 2005-184696, A

The detection light is applied to a position that is apart from the projection surface by a certain height, and depending on the angle at which the indicator points the projection surface, the instructed position and the position at which the detection light is reflected may shift.

On the other hand, the present invention relates to a technique for calculating the deviation between the instructed position and the position where the detection light is reflected.

The present invention provides a projection means for projecting an image on a projection surface, an irradiation means for irradiating detection light along the projection surface, and a position for detecting a first position which is the position of the detection light reflected by an indicator. The detection unit, the inclination detection unit that detects the inclination of the indicator with respect to the projection surface, the first position detected by the position detection unit, and the inclination detected by the inclination detection unit Provided is a projector including a calculation unit that calculates a shift between a second position that is a position of a specific portion and the first position.
According to this projector, it is possible to calculate the deviation between the instructed position and the position where the detection light is reflected.

This projector causes the projection means to project a specific image that prompts a user to instruct a specific point on the projection surface from the plurality of angles by the pointing device, and the pointing device sets the specific image in a state where the specific image is projected. When the specific point is designated, the position detecting unit detects the position of the indicator, and the tilt detecting unit detects the tilt of the indicator, and the specific point and the position detecting unit detect the tilt. Further, it may have a control means for executing a process of storing in the storage means a table recording the position of the indicator and the inclination of the indicator detected by the inclination detecting means.
According to this projector, it is possible to generate a table in which the deviation between the instructed position and the position where the detection light is reflected is recorded.

The indicator may include a sensor that detects the inclination of the indicator itself, and the inclination detector may obtain information indicating the inclination of the indicator from the indicator.
According to this projector, the tilt can be acquired from the pointer.

The present invention also includes the steps of projecting an image on a projection surface, irradiating the detection light along the projection surface, and detecting a first position which is the position of the detection light reflected by the pointer. A step of detecting an inclination of the indicator with respect to the projection surface; and a second position and a first position, which are positions of a specific portion of the indicator, based on the first position and the detected inclination. There is provided a projector control method including a step of calculating a deviation.
According to this control method, the shift between the instructed position and the position where the detection light is reflected can be calculated.

The figure which illustrates the functional composition of the projector 1 which concerns on one Embodiment. The figure which illustrates the hardware constitutions of the projector 1. The figure which shows the outline of detection light. The figure which shows the outline of detection light. The figure which illustrates the structure of the pen 21. 6 is a flowchart illustrating a correction table generation process according to an embodiment. The figure which illustrates the image for calibration. The figure which illustrates the gap of a specific position and a detection position. The figure which illustrates the produced|generated correction table. The flowchart which illustrates the correction process of a detection position.

1. Configuration FIG. 1 is a diagram illustrating a functional configuration of a projector 1 according to an embodiment. The projector 1 detects the position of the indicator 20 on the projection surface SC while projecting an image on the projection surface SC, and performs processing according to the detected position. The indicator 20 is a pen-shaped object or a user's finger. In this example, the projector 1 has a function of correcting the position of the indicator 20.

The projector 1 has a projection unit 11, an irradiation unit 12, a position detection unit 13, an inclination detection unit 14, a calculation unit 15, a storage unit 16, and a control unit 17. The projection means 11 projects an image on the projection surface SC. The irradiation unit 12 irradiates light for detecting the indicator 20 (hereinafter referred to as “detection light”) along the projection surface SC. The position detector 13 detects the first position, which is the position of the detection light reflected by the indicator 20. The tilt detecting means 14 detects the tilt of the indicator 20 with respect to the projection plane SC. The calculation unit 15 determines, based on the first position detected by the position detection unit 13 and the tilt detected by the tilt detection unit 14, a second position and a first position which are positions of a specific portion (for example, a tip) of the indicator 20. Calculate the deviation of

The storage unit 16 stores various data such as a table for correcting the position designated by the indicator 20 (hereinafter referred to as “correction table”). The control means 17 executes a process for generating a correction table. In this process, (1) the projection means 11 projects a specific image (hereinafter referred to as “calibration image”) that prompts the user to specify a specific point on the projection surface SC with the pointer 20 from a plurality of angles. 2) When the indicator 20 indicates a specific point in the state where the calibration image is projected, the position detector 13 is caused to detect the position of the indicator 20, and the tilt detector 14 is used to detect the indicator 20. The inclination is detected, and (3) a correction table in which the specific point, the position of the indicator 20 detected by the position detecting means 13, and the inclination of the indicator 20 detected by the inclination detecting means 14 are recorded is stored in the storage means 16. It is a process to do.

FIG. 2 is a diagram illustrating a hardware configuration of the projector 1. The projector 1 includes a CPU (Central Processing Unit) 100, a ROM (Read Only Memory) 101, a RAM (Random Access Memory) 102, an IF unit 104, an image processing circuit 105, a projection unit 106, an operation panel 107, a camera 108, and an optical unit. The irradiation unit 109 is included.

The CPU 100 is a control device that controls each unit of the projector 1. The ROM 101 is a non-volatile storage device that stores various programs and data. The ROM 101 stores a reference threshold value and a correction value described later. The RAM 102 is a volatile storage device that stores data, and functions as a work area when the CPU 100 executes processing.

The IF unit 104 is an interface that mediates the exchange of signals or data with external devices. The IF unit 104 is a terminal for exchanging signals or data with an external device (for example, VGA terminal, USB terminal, wired LAN interface, S terminal, RCA terminal, HDMI (High-Definition Multimedia Interface: registered trademark) terminal, Microphone terminal) and a wireless LAN interface. These terminals may include a video output terminal in addition to a video input terminal. The IF unit 104 may accept input of video signals from a plurality of different video supply devices.

The image processing circuit 105 performs predetermined image processing (for example, size change, trapezoidal correction, etc.) on the input video signal (hereinafter referred to as “input video signal”).

The projection unit 106 projects an image on the projection surface SC according to the image-processed video signal. The projection unit 106 has a light source, a light modulator, and an optical system (all not shown). The light source includes a lamp such as a high-pressure mercury lamp, a halogen lamp, or a metal halide lamp, a solid-state light source such as an LED (Light Emitting Diode) or a laser diode, and a driving circuit thereof. The light modulator is a device that modulates light emitted from a light source according to a video signal, and includes, for example, a liquid crystal panel or a DMD (Digital Mirror Device), and a drive circuit for these. The liquid crystal panel may be either a transmissive type or a reflective type. The optical system includes an element that projects the light modulated by the light modulator onto the projection surface SC, and includes, for example, a mirror, a lens, and a prism. The light source and the light modulator may be provided for each color component.

The operation panel 107 is an input device for a user to input an instruction to the projector 1, and includes, for example, a keypad, a button, or a touch panel.

The camera 108 is a camera for specifying the position of the pointer. In this example, the projector 1 can detect not only the user's finger but also a dedicated electronic pen as an indicator. The electronic pen has a light-emitting body (for example, an infrared light-emitting diode) provided on the tip of the pen, a pressure sensor, and a control circuit (all not shown). When the pressure sensor detects that the pen tip touches an object (projection surface or the like), the control circuit causes the light emitter to emit light in a predetermined light emission pattern. Alternatively, when it is detected that the pen tip touches the object, the control circuit may change the light emission pattern before and after the pen tip touches the object. The CPU 100 detects (specifies) the position of the pointer from the image captured by the camera 108. The CPU 100 can distinguish a plurality of indicators based on, for example, a difference in emission pattern or a difference in emission wavelength.

The light irradiation unit 109 emits detection light for detecting the user's finger. For example, infrared laser light is used as the detection light. The light irradiation unit 109 irradiates the laser beam in a curtain shape so as to cover the projection surface SC. The light irradiation unit 109 is a so-called light curtain unit. The light irradiation unit 109 has a light emitting element that emits laser light and an optical member for diffusing the laser light in a plane. The light irradiation unit 109 is housed in a housing independent of other elements, and communicates with the main body of the projector 1 by wire or wirelessly.

3 and 4 are diagrams showing the outline of the detection light. Here, the finger F of the user is shown as an example of the indicator 20. FIG. 3 is a schematic diagram of the projection surface SC viewed from the front. The detection light L is radially emitted from the light emitting unit 109 and covers the projection surface SC. FIG. 4 is a schematic view of the projection plane SC viewed from the cross-sectional direction. The detection light L is emitted along the projection surface SC at a height a little (for example, several mm) away from the projection surface SC. When the user's finger F approaches the projection surface SC, the detection light is reflected by the finger F. The position of the finger is detected by capturing this reflected light with the camera 108.

Referring back to FIG. In this example, the CPU 100 executes the program stored in the ROM 101, so that the functions shown in FIG. 1 are implemented in the projector 1. The projection unit 106 is an example of the projection unit 11. The light irradiation unit 109 is an example of the irradiation unit 12. The CPU 100 is an example of the position detection unit 13, the inclination detection unit 14, the calculation unit 15, and the control unit 17. The ROM 101 and the RAM 102 are an example of the storage unit 16.

FIG. 5 is a diagram illustrating the configuration of the pen 21. The pen 21 is an example of the indicator 20. The pen 21 has a gyro sensor 211 and a transmitter 212. The gyro sensor 211 is an example of a sensor that detects the inclination of the pen 21. The transmitter 212 transmits information indicating the tilt detected by the gyro sensor 211 to the projector 1. Note that the pen 21 is a pen that does not emit light itself, unlike the self-emission type electronic pen described for the camera 108.

2. Operation 2-1. Generation of Correction Table FIG. 6 is a flowchart illustrating a correction table generation process according to an embodiment. The flow of FIG. 6 starts, for example, when the user issues an instruction to generate or update the correction table (calibration or calibration). Here, an example in which the pen 21 is used as the indicator 20 will be described.

In step S11, the CPU 100 causes the projection unit 106 to project the calibration image. The data of the calibration image is stored in the ROM 101, for example. At this time, the detection light is also emitted.

FIG. 7 is a diagram illustrating a calibration image. The calibration image includes image objects O1 to O4. The image object O1 indicates a specific position. The image object O2 prompts the user to designate a specific position with the pen 21 from a plurality of angles. The image object O3 is for instructing the timing of acquiring the position and the inclination of the pen 21. The image object O4 is for instructing the end of calibration.

The user who views the calibration image picks up the pen 21 and touches the image object O1 with the pen tip (an example of a specific part) of the pen 21 at a certain angle with respect to the projection surface SC. With the pen tip touched, the user touches the image object O3 with another hand to instruct the position and inclination of the pen 21. Further, the user touches the image object O1 with the pen tip at another angle with respect to the projection surface SC. With the pen tip touched, the user touches the image object O3 again with another hand to instruct the position and inclination of the pen 21.

Referring back to FIG. In step S12, the CPU 100 determines whether the acquisition of the position and inclination of the pen 21 has been instructed. Whether or not the position and inclination of the pen 21 are instructed is determined by whether or not the position corresponding to the image object O3 is instructed. When it is determined that the acquisition of the position and the inclination of the pen 21 is not instructed (S12: NO), the CPU 100 waits until the acquisition of the position and the inclination of the pen 21 is instructed. When it is determined that the acquisition of the position and the inclination of the pen 21 is instructed (S12: YES), the CPU 100 shifts the processing to step S13.

In step S13, the CPU 100 acquires the position and inclination of the pen 21. The “position of the pen 21” here means the position of the detection light reflected by the pen 21 (hereinafter referred to as “detection position”; an example of the first position). The CPU 100 acquires the position of the pen 21 from the image captured by the camera 108. Further, the CPU 100 acquires the inclination of the pen 21 from the signal received from the pen 21 via the IF unit 104. The pen 21 transmits information indicating its own inclination to the projector 1 at a predetermined timing, and the RAM 102 stores this information. The CPU 100 acquires information indicating the inclination of the pen 21 from the RAM 102. Note that step S13 is an example of the step of detecting the first position, which is the position of the detection light reflected by the pointer, and the step of detecting the tilt of the pointer with respect to the projection surface.

In step S14, the CPU 100 calculates the deviation between the specific position and the detection position. Since the position of the specific point in the projected image is known on the data, the CPU 100 specifies the specific position from the data of the calibration image. Alternatively, the CPU 100 may specify the position of the specific point on the projection plane SC from the image captured by the camera 108. The specific position is considered to be substantially the same as the position of the pen tip of the pen 21.

FIG. 8 is a diagram exemplifying the deviation between the specific position and the detection position. FIG. 8 is a schematic diagram showing a cross section parallel to the projection plane SC. Since the projection plane SC is a two-dimensional plane, the deviation between the specific position and the detection position can be defined as a two-dimensional vector, but here, for simplification of explanation, only the one-dimensional deviation in a certain direction will be discussed. To do.

In this example, the pen 21 touches the projection surface SC at an angle α1. At this time, the detection position P1 is obtained with respect to the specific position P0. The deviation ΔP(α1) between the detection position P1 and the specific position P0 at the angle α1 is
ΔP(α1)=P1-P0 (1)
Is. In general, the deviation ΔP(αn) between the detection position Pn and the specific position P0 at the angle αn is
ΔP(αn)=Pn−P0 (2)
Is.

Referring back to FIG. In step S15, the CPU 100 stores the deviation ΔP(αn) calculated by the equation (2) in the RAM 102.

In step S16, the CPU 100 determines whether the end of calibration has been instructed. Whether or not the end of calibration is instructed is determined by whether or not the position corresponding to the image object O4 is instructed. When it is determined that the end of calibration has not been instructed (S16: NO), the CPU 100 shifts the processing to step S12. If it is determined that the end of calibration has been instructed (S16: YES), the CPU 100 shifts the processing to step S17.

In step S17, the CPU 100 integrates the deviation ΔP(αn) stored in the RAM 102 to generate a correction table. The CPU 100 stores the generated correction table in the ROM 101. If the correction table is already stored, the CPU 100 overwrites it. When the correction table is stored, the CPU 100 ends the flow of FIG.

FIG. 9 is a diagram illustrating an example of the generated correction table. For example, when the angle is 0°, ΔP(0°)=0, when the angle is +45°, ΔP(+45°)=+50, and when the angle is −45°, ΔP(−45°)=−50. According to this example, the deviation ΔP(αn) corresponding to various angles can be obtained.

2-2. Correction of Detection Position FIG. 10 is a flowchart illustrating the correction process of the detection position. The flow of FIG. 10 is started, for example, when the user gives an instruction to start processing according to the position of the pen 21. The process according to the position of the pen 21 is, for example, a drawing process of an image object according to the locus of the position of the pen 21. In the following, in order to distinguish the detection positions before and after the correction, the detection position before the correction and the detection position after the correction are referred to as “pre-correction detection position” and “post-correction detection position”, respectively.

In step S21, the CPU 100 detects the position and inclination of the pen 21. What is detected here is the pre-correction detection position. Specifically, the CPU 100 detects the position of the pen 21 from the image captured by the camera 108. Further, the CPU 100 acquires the inclination of the pen 21 from the signal received from the pen 21 via the IF unit 104.

In step S22, the CPU 100 corrects the position of the pen 21. Specifically, the CPU 100 reads the deviation ΔP(α) corresponding to the inclination α of the pen 21 from the correction table stored in the ROM 101. The CPU 100 obtains the post-correction detection position by subtracting the deviation ΔP(α) from the pre-correction detection position obtained in step S21.

The processes of steps S21 to S22 are repeatedly executed at a predetermined timing. According to this example, the position touched by the pen tip of the pen 21 can be detected more accurately.

3. Modifications The present invention is not limited to the above-described embodiment, and various modifications can be made. Hereinafter, some modified examples will be described. Two or more of the following modifications may be used in combination.

The method of detecting the tilt of the indicator 20 is not limited to the method exemplified in the embodiment. For example, the tilt of the indicator 20 may be detected from the image captured by the camera. In this case, the projector 1 has a camera for detecting the inclination of the indicator 20. This camera is provided at a position different from that of the camera 108, for example. As an example, when the projector 1 is installed on the projection surface SC, this camera is installed beside the projection surface SC. The CPU 100 specifies the outer shape of the indicator 20 from the image captured by this camera and calculates the inclination of the projection surface SC. In order to obtain the displacement as a two-dimensional vector, two or more cameras for detecting the tilt are provided, and the projection plane SC is photographed from different positions. In order to obtain the tilt more accurately, the positions of the two cameras are preferably separated (for example, near the upper side of the projection plane SC and near the right side), but a stereo camera may be used, for example. According to this example, it is possible to correct the detection position even with an indicator that does not have a function of detecting its own inclination, such as a user's finger.

Although the projection plane SC is a two-dimensional plane, the deviation may be corrected only in a specific direction, that is, one-dimensionally. For example, when it is known that the inclination of the indicator 20 is likely to occur only in a specific direction (for example, the vertical direction), this method is also useful.

The hardware configuration of the projector 1 for realizing the functions illustrated in FIG. 1 is not limited to the one illustrated in FIG. The projector 1 may have any hardware configuration as long as the required functions can be realized. For example, the projector 1 may include the light irradiation unit 109. Alternatively, the projector 1 may have a processor dedicated to detecting the position of the pointer.

DESCRIPTION OF SYMBOLS 1... Projector, 11... Projection means, 12... Irradiation means, 13... Position detection means, 14... Tilt detection means, 15... Calculation means, 16... Storage means, 17... Control means, 20... Pointer, 21... Pen, 100... CPU, 101... ROM, 102... RAM, 104... IF section, 105... Image processing circuit, 106... Projection unit, 107... Operation panel, 108... Camera, 109... Light irradiation section

Claims (4)

Projection means for projecting an image on the projection surface,
An irradiation unit that irradiates the detection light along the projection surface,
Position detection means for detecting a first position which is the position of the detection light reflected by the indicator,
Tilt detecting means for detecting the tilt of the pointer with respect to the projection surface,
Calculation means,
Control means,
Storage means
Have
The control means is
Causing the projection means to project a specific image that prompts the user to specify a specific point on the projection surface from the plurality of angles with the pointer,
When the pointer is pointing to the specific point in the state where the specific image is projected, the position detecting unit detects the position of the pointer, and the tilt detecting unit detects the tilt of the pointer. To detect
The calculation means is
When the indicator points to the specific point, the deviation between the first position detected by the position detection unit and the second position which is the position of the specific portion of the pointer is calculated,
The control means is
When the indicator indicates the specific point, the inclination of the indicator detected by the inclination detecting means and the shift calculated by the calculating means are recorded in a table in the storage means ,
When the position detection unit detects the position of the indicator with an image other than the specific image projected, the control unit detects the tilt detection unit from a table stored in the storage unit. A projector that reads out a shift corresponding to the tilt and obtains the position of the specific portion of the indicator using the position detected by the position detection unit and the shift . Projection means for projecting an image on the projection surface,
An irradiation unit that irradiates the detection light along the projection surface,
Position detection means for detecting a first position which is the position of the detection light reflected by the indicator,
Tilt detecting means for detecting the tilt of the pointer with respect to the projection surface,
Calculation for calculating the deviation between the second position and the first position, which is the position of the specific portion of the indicator, from the first position detected by the position detection unit and the tilt detected by the tilt detection unit And means,
The indicator has a sensor that detects the inclination of the indicator,
A projector in which the tilt detection unit acquires information indicating a tilt of the pointer from the pointer. The projection means projects an image on the projection surface,
Position detecting means, irradiating the detection light along the projection surface,
The position detecting means detects a first position, which is a position of the detection light reflected by the indicator,
A step of detecting a tilt of the indicator with respect to the projection plane,
A step in which the projection means projects a specific image that prompts the user to instruct a specific point on the projection surface from a plurality of angles with the indicator;
When the pointer is pointing to the specific point in the state where the specific image is projected, the position detecting unit detects the position of the pointer, and the tilt detecting unit detects the tilt of the pointer. To detect
A step of calculating a deviation between the first position detected by the position detecting means and a second position which is a position of a specific part of the indicator when the indicator points the specific point;
When the indicator points to the specific point , the storage unit records the tilt of the pointer detected by the step of detecting the tilt and the shift calculated by the calculating step in a table,
When the position detection unit detects the position of the indicator in a state where an image other than the specific image is projected, the control unit detects the tilt from the table stored in the storage unit. A method of controlling the projector , comprising: reading a shift corresponding to the tilt, and obtaining the position detected by the position detection unit and the position of the specific portion of the indicator using the shift . The step of projecting an image on the projection surface,
Irradiating detection light along the projection surface,
Detecting a first position, which is the position of the detection light reflected by the indicator,
Detecting a tilt of the indicator with respect to the projection surface,
Calculating a shift between the first position and a second position, which is a position of a specific portion of the indicator, from the first position and the detected inclination,
The indicator has a sensor that detects the inclination of the indicator,
A method of controlling a projector , wherein in the step of detecting the tilt, the control means acquires information indicating the tilt of the pointer from the pointer.

Images