JP2007264413A - Projector, projection method and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To restrain a blur by achieving an image correction in which projected images are corrected even if a projection surface is not smooth. <P>SOLUTION: This projector comprises: a projection section that projects images to the projection surface; a focusing section that focuses images to be projected by the projection section; a distance measurement section that measures the distances of at least three measurement positions in the display range of an image displayed on the projection surface; and a control section that controls the projection section and focusing section based on the measurement results of the distance measurement section. From the measurement results of the distance measurement section obtained in the corresponding measurement positions, the control section determines whether the measurement positions are on the same plane or not. If they are not on the same plane, an imaginary plane is calculated based on the measured distance of each measurement position. Also, the focusing section is controlled so that an image projected by the projection section is focused on the imaginary plane. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projection apparatus, a projection method, and a program, and more particularly, to a projection apparatus, a projection method, and a program capable of correcting a projection image.

Conventionally, in a projection device that projects an image on a wall surface, a screen or the like, for example, when the projector is installed with an inclination with respect to a projection surface such as a wall surface or a screen, the inclination is detected and the projected image is corrected. A device that displays a suitable projection image has been developed (see, for example, Patent Document 1).
JP 2005-70415 A

  However, in the projection apparatus described in Patent Document 1, although correction is performed corresponding to only the inclination of the projection surface, since the unevenness on the projection surface is not taken into consideration, there is unevenness on the projection surface. In such a case, a suitable projection image has not been formed. In particular, in most cases, the concave portion or the convex portion on the projection surface is in focus. For example, when the concave portion is in focus, the image is blurred on the convex portion.

  The subject of this invention is implement | achieving the image correction | amendment by which a projection image is corrected also with respect to the unevenness | corrugation of a projection surface, and is suppressing blurring.

The projection apparatus according to claim 1,
Projection means for projecting an image onto the projection plane;
Focusing means for focusing an image projected by the projection means;
Distance measuring means for measuring each distance to at least three measurement positions of the projection plane;
Control means for controlling the projection means and the focusing means based on the measurement result of the distance measuring means,
The control means determines whether or not the measurement positions are on the same plane from the measurement results of the distance measurement means at the plurality of positions, and if they are not on the same plane, A virtual plane is calculated based on the measurement distance, and the focusing unit is controlled so that an image projected by the projection unit is focused on the virtual plane.

A second aspect of the present invention is the projection apparatus according to the first aspect,
The control means includes
For each distance measured by the distance measuring means at each measurement position, an intermediate between the optical axis component distance at which the optical axis direction component distance of the projection optical axis direction component is maximum and the optical axis component distance at which the optical axis component distance is minimum. The virtual plane is calculated so that the virtual plane is arranged at a position where the measurement position group corresponding to the optical axis component distance as a value exists.

According to a third aspect of the present invention, in the projection apparatus according to the first aspect,
The control means includes
For each distance measured by the distance measuring means at each measurement position, an average value of the optical axis direction component distances of the projection optical axis direction components is taken, and the virtual plane is located at the position where the measurement position group serving as the average value exists. The virtual plane is calculated so as to be arranged.

According to a fourth aspect of the present invention, in the projection apparatus according to the first aspect,
The control means is characterized in that, when it is determined that the measurement positions are on the same plane for a predetermined ratio or more, the plane is set as a virtual plane.

The projection method of the invention according to claim 5 is:
A projection step of projecting an image onto the projection plane;
A distance measuring step for measuring distances to at least three measurement positions on the projection plane;
A focusing step of focusing the image to be projected on the projection plane,
The focusing step includes
It is determined whether or not the measurement positions are on the same plane from the measurement results of the measurement positions obtained by the ranging step. If the measurement positions are not on the same plane, the measurement results of the measurement positions are determined. A virtual plane is calculated based on the above, and the projected image is focused on the virtual plane.

The program of the invention described in claim 6 is:
A projecting step for projecting an image onto a projection surface;
A ranging step of measuring each distance to at least three measurement positions on the projection plane;
A focusing step of focusing the image to be projected on the projection plane,
The focusing step includes
It is determined whether or not the measurement positions are on the same plane from the measurement results of the measurement positions obtained by the ranging step. If the measurement positions are not on the same plane, the measurement results of the measurement positions are determined. A virtual plane is calculated based on the above, and the projected image is focused on the virtual plane.

  According to the present invention, it is determined whether or not at least three measurement positions are on the same plane, and if they are not on the same plane, that is, if there is an unevenness in the display range of the image displayed on the projection plane Since the virtual plane is calculated based on each measurement distance of the measurement position and the image is focused on the virtual plane, it is possible to prevent the concave portion or the convex portion on the projection surface from being focused. . As a result, it is possible to suppress blurring of the projected image.

[First Embodiment]
Hereinafter, a first embodiment according to the present invention will be described with reference to the drawings. The projection apparatus according to the present embodiment includes a projection unit that projects an image on a projection plane, a focusing unit that focuses an image projected by the projection unit, and a display range of an image displayed on the projection plane. A distance measuring unit that measures each distance to at least three measurement positions, and a control unit that controls the projection unit and the focusing unit based on the measurement results of the distance measuring unit are provided. Then, the control unit determines whether or not all the measurement positions are on the same plane from each measurement result of the distance measurement unit at a plurality of positions, and if not, the measurement distance of each measurement position A virtual plane is calculated based on the above, and the focusing unit is controlled so that the image projected by the projection unit is focused on the virtual plane.

  The projector according to the present invention will be specifically described. FIG. 1 shows an external configuration of a projector device as a projection device. FIG. 1A is a perspective view showing an upper side of the projector device, and FIG. 1B is a perspective view showing a lower side of the projector device.

  As shown in FIG. 1, the projector device 10 is provided with a projection lens 12, two pairs of distance measuring lenses 13 a, 13 b, 13 c, 13 d and an Ir transmission / reception unit 14 on the front surface of a rectangular parallelepiped main body casing 11. .

  The projection lens 12 is for projecting a light image formed by a spatial optical modulation element such as a micromirror element to be described later. Here, the focus position and the zoom position (projection angle of view) can be arbitrarily changed. Shall.

  Of the two pairs of distance measuring lenses 13a, 13b, 13c, and 13d, the pair of distance measuring lenses 13a and 13b are disposed along the vertical direction, and the other pair of distance measuring lenses 13c and 13d are horizontally aligned. It is arranged along. These distance measuring lenses 13a, 13b, 13c, and 13d constitute part of phase difference sensors 131 and 132, which will be described later, respectively, and are based on the principle of triangulation based on the parallax between these two lenses with respect to the subject image. Then, the distance to the subject, specifically, the distance to the projected image plane is measured.

  The Ir transmission / reception unit 14 receives infrared light on which a key operation signal from a remote controller 40 described later is superimposed and transmits an instruction signal to the remote controller 40.

A cover 17 and an indicator 15 are disposed on the upper surface of the main body casing 11.
The cover 17 is opened and closed when operating a main body subkey (not shown). The main body sub key can operate various detailed operations that cannot be set by the key of the indicator 15 without using the remote controller 40.

  An input unit 18, an Ir transmission / reception unit 19, and an AC adapter connection unit 20 are disposed on the back surface of the main body casing 11.

  The input unit 18 is, for example, a USB terminal for video input / output connection with an external device such as a personal computer, a mini D-SUB terminal for video input, an S terminal and an RCA terminal, a stereo mini terminal for audio input, and the like. Consists of.

  The Ir transmitter / receiver 19 receives the infrared light on which the key operation signal from the remote controller 40 is superimposed, as well as the Ir transmitter / receiver 14, and transmits an instruction signal to the remote controller 40.

  The AC adapter connection unit 20 is connected with a cable from an AC adapter (not shown) serving as a power source.

A pair of fixed legs 21 and 21 are attached to the lower surface of the main body casing 11 on the rear side, and an adjustment leg 22 capable of height adjustment is attached to the front side.
The adjustment leg 22 is configured to adjust the vertical component of the projection direction of the projection lens 12, that is, the elevation angle, by manipulating the screw rotation position manually.

  Next, the indicator 15 will be described with reference to FIG. FIG. 2 is an explanatory diagram showing the key layout and the like of the indicator 15. As shown in FIG. 2, the indicator 15 includes a power key 15a, a zoom key 15b, a focus key 15c, an “AFK” key 15d, an “Input” key 15e, an “Auto” key 15f, and a “menu”. ”Key 15 g,“ Adjust ”key 15 h,“ HELP ”key 15 i,“ Esc ”key 15 j,“ Up (↑) ”key 15 k,“ Down (↓) ”key 15 l,“ Left (←) ”key 15 m,“ A “write (→)” key 15n, an “Enter” key 15o, a power / standby indicator 15p, and a temperature (TEMP) indicator 15q are provided.

The power key 15a instructs on / off of the power.
The zoom key 15b instructs zoom-in (tele) and zoom-down (wide) by operating “Δ” and “▽”.

The focus key 15c instructs to move the in-focus position forward and backward by the operation of “Δ” and “▽”.
The “AFK” key 15d instructs immediate execution of various processes such as automatic focusing.

  The “Input” key 15 e instructs manual switching of the image signal input to any of the input units 18, and the “Auto” key 15 f automatically switches the image signal input to any of the input units 18. Instruct.

The “menu” key 15g instructs display of various menu items related to the projection operation, and the “Adjust” key 15h instructs the start of analysis processing for detecting the state of the projection plane.
The “HELP” key 15i instructs display of various help information when the instruction operation is unknown, and the “Esc” key 15j instructs release of the operation at that time.

  The “up” key 15k, the “down” key 15l, the “left” key 15m, and the “right” key 15n are operated in accordance with a menu item, a pointer, a cursor, or the like when a selection or movement direction is instructed at that time. In addition to these, an “up” key 15k, a “down” key 15l, a “left” key 15m, and a “right” key 15n are used to input the presentation presentation time, and to page the projected image. Is operated. As described above, the “up” key 15k, the “down” key 15l, the “left” key 15m, and the “right” key 15n are the registration unit according to the present invention in which the presentation presentation time is registered.

The power / standby indicator 15p displays a power on / off state and a state in which no image signal is input, for example, by turning on / off or blinking green and red LEDs.
The temperature indicator 15q displays whether or not the temperature of a lamp serving as a light source for image projection is in a state suitable for projection, for example, by turning on / off or blinking green and red LEDs.

Next, the remote controller 40 will be described. FIG. 3 is an explanatory diagram showing the key arrangement and the like of the remote controller 40. As shown in FIG. 3, similarly to the indicator 15, the remote controller 40 includes a power key 40a, a zoom key 40b, a focus key 40c, an “AFK” key 40d, an “Input” key 40e, and “Auto”. ”Key 40f,“ menu ”key 40g,“ Adjust ”key 40h,“ HELP ”key 40i,“ Esc ”key 40j,“ Up (↑) ”key 40k,“ Down (↓) ”key 40l,“ Left (← ) ”Key 40m,“ write (→) ”key 40n, and“ Enter ”key 40o.
Each of these keys outputs an instruction similar to each key of the corresponding indicator 15.

  FIG. 4 is a block diagram illustrating a functional configuration of the electronic circuit of the projector device 10. As shown in FIG. 4, the projector device 10 is provided with a projection unit (projection unit) 50 that projects an image. The projection unit 50 includes a display encoder 33, a video RAM 34, a display drive unit 35, a display element 36, a light source unit 37, the projection lens 12, and a lens motor (M) 38.

FIG. 5 is a block diagram illustrating a specific schematic configuration of the projection unit 50.
The light source unit 37 includes a light source lamp 61, a reflector 62 that reflects light emitted from the light source lamp 61 in a direction for condensing the light forward, and a luminance distribution of light emitted forward of the reflector 62. A light guide member 63 is provided.

  The light guide member 63 is made of a transparent rectangular bar made of glass or the like, and has one end as an incident end of light and the other end as an exit end of light incident from the incident end. The light guide member 63 is disposed with its incident end opposed to the exit surface of the reflector 62. The light emitted from the incident end is incident on the front side of the reflector 62, and the light is guided while being reflected internally. Light having a uniform luminance distribution is emitted from the emission end.

  In addition, the color wheel 64 disposed on the emission side of the light source unit 37 is arranged around the central member 67 rotated at a low speed by the motor 65 in the circumferential direction thereof, and includes at least one space part without the color filters and the color filter. Are provided. The color wheel 64 has its wheel surface aligned with the condensing point of the emitted light from the light source unit 37, and a part of the circumference in which the color filters and the spaces of the plurality of colors are arranged is the optical path of the emitted light from the light source unit 37. It is arranged to intersect.

  The display element 36 is a micromirror element made of ultrathin metal pieces each having a vertical and horizontal width of 10 to 20 μm. The micromirror element has a display area in which a plurality of pixels formed by micromirrors tilted in one direction and the other by a mirror drive element based on COMS are arranged in a row direction and a column direction. The light incident at a predetermined incident angle from the incident direction inclined in one direction with respect to the front direction is reflected in one of the display observation direction and the other direction by switching the inclination direction of the micromirror, and a plurality of An image is displayed by controlling the emission of light from the pixel in the observation direction.

Between the display element 36 and the light source unit 37, a light source side lens 71 that corrects the emitted light from the light source unit 37 in parallel and enters the display element 36 is disposed. The projection lens 12 projects the light emitted from the display element 36 in the observation direction on a projection surface such as a screen by enlarging the luminous flux.
In the present embodiment, each of the light source side lens 71 and the projection lens 12 is illustrated as a single lens, but each of the light source side lens 71 and the projection lens 12 includes a plurality of lenses in order to reduce lens aberration. It is configured by combining.

Further, the display driving unit 35 that controls the display element 36 is synchronized with the rotation of the color wheel 64 when the color filter of each color of the color wheel passes through the optical path of the emitted light from the light source unit 37. A monochromatic image of a color component corresponding to each color is displayed on the display element 27, and light from a plurality of pixels of the display element 36 is displayed when the space portion of the color wheel 64 passes through the optical path of the emitted light from the light source unit 37. Adjust the emission time.
The display drive unit 35 includes a color wheel control unit 68, a time division drive circuit 69, and a color sequence control circuit 70.

  The color wheel control unit 68 controls a motor 65 that rotates the color wheel 64 in synchronization with a timing signal given from the time-division drive circuit 69. The motor 65 is controlled by the color wheel control unit 68, The color wheel 64 is rotated at a constant speed.

  The time-division drive circuit 69 gives a timing signal to the color wheel control unit 68 according to the display mode signal sent from the color sequence control circuit 70, and each of red, green, and blue color components given from an external circuit (not shown). A monochrome image signal W is generated by matrix calculation based on the monochrome image signals R, G, and B, and the monochrome image signals R, G, and B of the respective color components of red, green, and blue are synchronized with the rotation of the color wheel 64. And the monochrome image signal W are sequentially supplied to the display element 36.

  That is, the time division drive circuit 69 corresponds to the color of the color filter when the color filter of the color wheel 64 passes through the optical path of the emitted light from the light source unit 37 in synchronization with the rotation of the color wheel 64. The monochrome image signals R, G, and B of the color component are supplied to the display element 36 to display a monochrome image, and when the space portion of the color wheel 64 passes the optical path of the emitted light from the light source unit 37, the monochrome image signal W is supplied to the display element 36 to control light emission from a plurality of pixels of the display element 36.

  Further, the time-division drive circuit 69 adjusts the supply time of the monochrome image signal W to the display element 36 in accordance with the display mode signal from the color sequence control circuit 70, and during the supply time of the image signal W, the display element A monochrome image corresponding to the monochrome image signal W is displayed on 36.

  That is, the time-division drive circuit 69 determines the light emission time from the plurality of pixels of the display element 36 when the space portion of the color wheel 64 passes through the optical path of the light emitted from the light source unit 37. Adjust according to the supply time.

  In this embodiment, as described above, the emitted light from the light source unit 37 is changed in the order of green light, blue light, red light, and non-colored light while the color wheel 64 rotates once. Therefore, the time-division drive circuit 69 supplies the display element 36 with a green monochrome image signal, a blue monochrome image signal, a red monochrome image signal, and a monochrome image signal in order.

  The color sequence control circuit 70 sends a display mode signal for designating the brightness of the projection image selected by the user of the projection display device to the time division drive circuit 69.

  As shown in FIG. 4, image signals of various standards input from the input unit 18 of the projector device 10 and image signals based on image data in the storage unit 60 described later are input / output interfaces (I / F) 31. Then, after being unified into an image signal of a predetermined format by the image conversion unit 32 via the system bus SB, it is sent to the display encoder 33.

  The display encoder 33 develops and stores the transmitted image signal in the video RAM 34, generates a video signal from the stored contents of the video RAM 34, and outputs the video signal to the display drive unit 35.

  The display driver 35 controls the display element 36 as described above at an appropriate frame rate, for example, 30 [frames / second] in accordance with the transmitted image signal.

The projection lens 12 is driven by a lens motor (M) 38 to appropriately move the zoom position and the focus position. That is, the projection lens 12 and the lens motor 38 are focusing means according to the present invention that focuses the image projected by the projection unit 50.
A control unit (control means) 39 controls all the operations of the circuits. The control unit 39 includes a CPU, a ROM that stores an operation program fixedly, a RAM that is used as a work memory, and the like.

A storage unit 60, a sound processing unit 41, an acceleration sensor 42, and a distance measuring unit (ranging unit) 43 are connected to the control unit 39 via a system bus SB.
The storage unit 60 is composed of, for example, a flash memory and stores image data and the like. The storage unit 60 appropriately reads out image data instructed by the control unit 39 and sends the image data to the display encoder 33. Projected display.

The sound processing unit 41 includes a sound source circuit such as a PCM sound source, converts the sound data given during the projection display operation into an analog signal, and drives the speaker 16 to emit a loud sound.
The acceleration sensor 42 detects the vibration when the projector device 10 is moved from the installed state, and outputs a detection signal to the control unit 39.

  The distance measuring unit 43 drives the phase difference sensor 131 having the distance measuring lenses 13a and 13b and the phase difference sensor 132 having the distance measuring lenses 13c and 13d, respectively, to determine the distances to any plurality of positions in the projected image. taking measurement.

  Here, the distance measuring method by the distance measuring unit 43 will be described in detail. In the following description, among the phase difference sensor 131 provided in the projector device 10 and the phase difference sensor 132, the phase difference sensor 132 for horizontal distance measurement will be described as an example, but the phase difference for vertical distance measurement will be described. The same applies to the sensor 131.

  FIG. 6 is a top view illustrating a schematic configuration of the phase difference sensor 132. As shown in FIG. 6, the phase difference sensor 132 is provided with a pair of distance measuring lenses 13 c and 13 d and a pair of photo sensor arrays 51 and 52 arranged to face the distance measuring lenses 13 c and 13 d. .

  When measuring the distance from the phase difference sensor 132 to the subject 53, the reflected light of the light irradiated to the subject 53 forms an image on the photosensor array 51 through one distance measuring lens 13c, and the reflected light is The image is formed on the photosensor array 52 through the other distance measuring lens 13d. 54 and 55 in the figure indicate the subject images.

The distances between the optical axes of the distance measuring lenses 13c and 13d and the imaging are x1 and x2, the distance between the distance measuring lenses 13c and 13d is B, and the distance between the photosensor arrays 51 and 52 and the distance measuring lenses 13c and 13d. And the distance d to the subject 53 is obtained by the following equation.
d = B · f / (x1 + x2) (1)
In this equation (1), since B and f are values unique to the sensor, the distance d to the object 53 is determined by the phase (x1, x2) of the photosensor arrays 51, 52.

  Next, multipoint ranging will be described. FIG. 7 is an explanatory diagram for explaining multipoint ranging. As shown in FIG. 7, the pair of photosensor arrays 51 and 52 of the phase difference sensor 132 is configured by a line sensor having several hundred bits of photosensors arranged in a row. Multipoint ranging is a method in which these photosensors are divided into a plurality of groups and a ranging sensor is performed for each group.

  In the example of FIG. 7, the distance (projection light) from at least three measurement positions (left side, center, right side) in the display range of the image displayed on the projection plane to the phase difference sensor 132 in the direction perpendicular to the projection plane. This shows the case of measuring the axial component distance of the axial component). Specifically, the photosensors in the photosensor arrays 51 and 52 are divided into three groups, respectively, and the photosensors of the A1 and A2 groups located on the left side measure the right side toward the screen 56, and B1 located in the center. And B2 group photo sensors measure the vicinity of the center of the screen 56, and the C1 and C2 group photo sensors located on the right side measure the left side of the screen 56.

  FIG. 8 is an explanatory diagram showing the positional relationship between the phase difference sensor and the screen. As shown in FIG. 8, when the screen 56 (solid line portion) is in parallel with the phase difference sensor 132, the phase difference between the three measurement points on the right side, center, and left side of the screen 56 is D = The relationship E = F holds.

  On the other hand, when the screen 56 is tilted by θ as shown by the dotted line in the figure, when the three measurement points on the right side, the center, and the left side of the screen 56 are measured (D ′, E ′, F ′), the phase difference is The relationship is D ′ <E ′ <F ′. In this case, since the screen 56 is a plane, these three points can be expressed as a linear straight line, and the inclination angle of the screen 56 from the distance between the three points, that is, the inclination of the image projected on the screen 56. The angle can be determined.

  FIG. 9 is an explanatory diagram showing the positional relationship between the phase difference sensor and the uneven wall surface. As shown in FIG. 9, the wall surface 57 is provided with irregularities such as pillars 58, for example. In such a case, the phase difference sensor 132 measures the three measurement points (G, H, I) on the right side, center, and left side of the wall surface, and measures from each measurement position to the phase difference sensor 132 by these phases. The distances d1, d2, and d3 (here, d1 = d3> d2) are obtained.

  From the measurement results at a plurality of positions obtained by the distance measuring unit 43 by this method, the control unit 39 determines whether or not each measurement position is on the same plane. A virtual plane is calculated based on each measurement distance of the position. In this calculation, each measurement result is arranged at a position that is an intermediate value M between the maximum measurement value (d1, d3) and the minimum measurement value (d2) in the direction perpendicular to the projection plane. Calculate the virtual plane. The calculated virtual plane V is a dotted line portion in FIG.

  The control unit 39 drives the projection lens 12 by controlling the lens motor 38 of the focusing unit so that the image projected by the projection unit 50 is focused on the virtual plane V.

  When a key operation signal is input to the control unit 39 by the indicator 15 or the remote controller 40, the control unit 39 controls each drive unit based on the signal.

  Next, the operation of this embodiment will be described. FIG. 10 is a flowchart showing an example of a program according to the present invention that is executed by the projector device 10 of the present embodiment. By executing this program, the projection method according to the present invention is realized.

When an analysis process start instruction is input from the “Adjust” key 15h, the control unit 39 executes the program.
In step S1, the control unit 39 controls the distance measurement unit 43 to measure the distance to each measurement position, and converts the distance into the projection direction distance from the distance measurement direction and the measurement result (distance measurement step, distance measurement step). ).

  In step S2, the control unit 39 determines whether each measurement position exists on the same plane by comparing the projection direction distances calculated in step S1. When all the projection direction distances are the same, the control unit 39 recognizes that each measurement position is on the same plane, and proceeds to step S4, and when all the projection direction distances are not the same. Recognizes that each measurement position does not exist on the same plane, and proceeds to step S3.

In step S3, the control unit 39 calculates a virtual plane that is a plane for focusing by a predetermined method. In the calculation of the virtual plane, as described above, a plane perpendicular to the projection direction at a distance between the maximum value and the minimum value of the projection direction distance may be set as the virtual plane, or the average value of each projection direction distance may be calculated. A plane perpendicular to the projection direction at a distance may be a virtual plane.
In addition, when the projection apparatus has a function that can change the projection direction, such as a lens shift function, the virtual plane is calculated in consideration of not only the projection direction distance but also the distance measurement direction, and is perpendicular to the changed projection direction. It can also be a flat surface. Thereby, it is possible to obtain a projection image in which blurring is further suppressed.

  In step S4, the control unit 39 adjusts the focus by controlling the lens motor 38 and moving the projection lens 12 so as to project the image while focusing on the determined projection plane. This projection plane is the plane when each measurement position is on the same plane, and is the calculated virtual plane otherwise (focusing step, focusing step).

  In step S5, the control unit 39 projects a chart for performing keystone correction.

  In step S6, the control unit 39 performs trapezoidal correction (auto keystone correction) based on the projected chart.

  In step S7, the control unit 39 controls the projection unit 50 to project an image onto the projection plane (projection step, projection process).

  As described above, in the present embodiment, it is determined whether or not the three measurement positions are on the same plane. If the three measurement positions are not on the same plane, that is, unevenness is present in the display range of the image displayed on the projection plane. If there is, the virtual plane is calculated based on each measurement distance of the measurement position, and the image is focused on the virtual plane, so that the concave portion or the convex portion on the projection surface is prevented from being focused. be able to. As a result, it is possible to suppress blurring of the projected image.

  In the above, the processing is executed in the order of the distance measuring step → the focusing step → the projecting step. However, the present invention is not limited to this, and if the focusing step is executed after the distance measuring step, the projection step may be performed before and after. It doesn't matter. For example, there may be a projection step before the distance measurement step, and there may be a case where there is a projection step between the distance measurement step and the focusing step. That is, the image may be projected first, the distance measurement step and the focusing step may be performed later, and the focus may be adjusted later. This makes it possible to project an image as soon as possible.

  Further, the control unit 39 virtually sets the measurement result of the distance measurement unit 43 at the three measurement positions at a position that is an intermediate value between the maximum measurement value and the minimum measurement value in the direction perpendicular to the projection plane. Since the virtual plane is calculated so that the plane is arranged, when the image is focused on the virtual plane, either the measurement position with the maximum value or the measurement position with the minimum value is selected. In this case, the blur of the projected image can be suppressed as much as possible.

Of course, the present invention is not limited to the above-described embodiment and can be modified as appropriate.
For example, in the present embodiment, a projector device as a front projector is described as an example, but the present invention can also be applied to a rear projector.
Further, in the present embodiment, the case where the number of measurement positions is three is illustrated, but the number of measurement positions may be four or more. If the number of measurement positions is increased, the plane detection accuracy of the projection plane increases accordingly. For example, FIG. 11 shows a case where three pillars 58 are arranged on the projection surface (wall surface 57), and FIG. 12 shows a case where the projection surface 59 is wavy, but there are three measurement positions. In the case of (L1, L2, L3 in the figure), the measurement results at each measurement position are the same in both cases of FIGS. 11 and 12 (in the case of FIG. 11, the measurement results are D1 and FIG. 12). In the case of (2), the measurement result is determined as D2), which is a plane. However, for example, if L4 and L5 in the figure are added and the measurement positions are five, the measurement results at all the measurement positions will be different, so this projection plane is determined not to be a plane. .

  Further, in the present embodiment, among the measurement results of the distance measuring unit 43 at at least three measurement positions, the position is an intermediate value between the maximum measurement value and the minimum measurement value in the direction perpendicular to the projection plane. Although the case where the virtual plane is arranged has been described as an example, the virtual plane may be arranged at a position that is an average value of each measurement result of the distance measuring unit 43 at each measurement position. Thereby, another form for suppressing blurring on the projection plane when the image is focused on the virtual plane can be provided.

And in this embodiment, the virtual plane is calculated based on the measurement result of each measurement position, but when the difference between the minimum value and the maximum value of the measurement result of each measurement position exceeds the allowable range, An error or warning may be notified. As described above, if the projection surface has an allowable range of unevenness, it is possible to avoid projecting the projection surface as it is when the projection surface is extremely uneven.
In addition, even when the difference between the minimum value and the maximum value of the measurement results at each measurement position described above exceeds the allowable range, the virtual plane may be forcibly arranged at a position where the above average value is obtained. . As a result, it is possible to project an image with automatic focus adjustment even in a place where the unevenness is extremely severe.

  In the case of measuring a number of points, if it is known that a predetermined ratio (for example, 80%) is in the same plane, the rest are ignored and the same plane is ignored. You may make it project. As a result, even if a part of the projection surface protrudes from the screen or only a very small part of the projection surface protrudes extremely, the projected image is not blurred, and the focus is reduced. Projected images can be projected.

  In this embodiment, a phase difference sensor is used for distance measurement, but a distance image sensor may be used. The distance image sensor is, for example, a CMOS sensor having a special pixel structure based on a “charge transfer method” in which charges accumulated in a pixel are read out as a voltage, transferred to an output circuit, amplified and output, and around the CMOS sensor. And an LED that irradiates near-infrared light toward a subject, and uses a “TOF method” in which a distance is obtained by measuring the time until the CMOS receives the reflected LED light. This makes it possible to quickly perform ranging over a wider range.

  In addition, this invention is not limited to embodiment mentioned above, In the implementation stage, it can change variously in the range which does not deviate from the summary. Further, the functions executed in the above-described embodiments may be combined as appropriate as possible. The above-described embodiments include various stages of the invention, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if several constituent requirements are deleted from all the constituent requirements shown in the embodiment, if an effect can be obtained, a configuration from which the constituent requirements are deleted can be extracted as an invention.

It is a perspective view which shows the external appearance structure of the projector apparatus as a projection apparatus of this embodiment. It is explanatory drawing showing the keyboard layout etc. of the indicator with which the projector apparatus of FIG. 1 is provided. It is explanatory drawing showing the keyboard layout etc. of the remote controller with which the projector apparatus of FIG. 1 is equipped. It is a block diagram showing the function structure of the electronic circuit of the projector apparatus of FIG. FIG. 2 is a block diagram illustrating a specific schematic configuration of a projection unit provided in the projector apparatus of FIG. 1. FIG. 6 is a top view illustrating a schematic configuration of a phase difference sensor provided in the projection unit of FIG. 5. It is explanatory drawing for demonstrating the multipoint ranging used with the projector apparatus of FIG. It is explanatory drawing showing the positional relationship of the phase difference sensor with which the projection part of FIG. 5 is provided, and a screen. It is explanatory drawing showing the positional relationship of the phase difference sensor of FIG. 8, and an uneven | corrugated wall surface. It is a flowchart showing an example of the program performed with the projector apparatus 10 of this embodiment. It is explanatory drawing showing the positional relationship of the phase difference sensor of FIG. 8, and the wall surface which has three pillars. It is explanatory drawing showing the positional relationship of the phase difference sensor of FIG. 8, and the waved projection surface.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Projector apparatus 11 Main body casing 12 Projection lens (focusing means)
13a, 13b, 13c, 13d Distance lens 14 Ir transmission / reception unit 15 Indicator 16 Speaker 17 Cover 18 Input unit 19 Ir transmission / reception unit 20 Adapter connection unit 21 Fixed leg unit 22 Adjustment leg unit 27 Display element 32 Image conversion unit 33 Display encoder 34 Video RAM
35 Display drive unit 36 Display element 37 Light source unit 38 Lens motor (focusing means)
39 Control Unit 40 Remote Controller 41 Audio Processing Unit 42 Acceleration Sensor 43 Distance Measuring Unit 50 Projection Unit 51 Photo Sensor Array 51, 52 Photo Sensor Array 53 Subject 56 Screen 60 Storage Unit 61 Light Source Lamp 62 Reflector 63 Light Guide Member 64 Color Wheel 65 Motor 67 Central member 68 Color wheel controller 69 Time division drive circuit 70 Color sequence control circuit 71 Light source side lens 131, 132 Phase difference sensor

Claims (6)

Projection means for projecting an image onto the projection plane;
Focusing means for focusing an image projected by the projection means;
Distance measuring means for measuring each distance to at least three measurement positions of the projection plane;
Control means for controlling the projection means and the focusing means based on the measurement result of the distance measuring means,
The control means determines whether or not the measurement positions are on the same plane from the measurement results of the distance measurement means at the plurality of positions, and if they are not on the same plane, A projection apparatus that calculates a virtual plane based on a measurement distance and controls the focusing unit so that an image projected by the projection unit is focused on the virtual plane. The projection device according to claim 1,
The control means includes
For each distance measured by the distance measuring means at each measurement position, an intermediate between the optical axis component distance at which the optical axis direction component distance of the projection optical axis direction component is maximum and the optical axis component distance at which the optical axis component distance is minimum. A projection apparatus, wherein the virtual plane is calculated so that the virtual plane is arranged at a position where the measurement position group corresponding to the optical axis component distance as a value exists. The projection device according to claim 1,
The control means includes
For each distance measured by the distance measuring means at each measurement position, an average value of the optical axis direction component distances of the projection optical axis direction components is taken, and the virtual plane is located at the position where the measurement position group serving as the average value exists. The projection apparatus is characterized in that the virtual plane is calculated such that The projection device according to claim 1,
When the control means determines that the measurement positions are on the same plane by a predetermined ratio or more, the projection apparatus sets the plane as a virtual plane. A projection step of projecting an image onto the projection plane;
A distance measuring step for measuring distances to at least three measurement positions on the projection plane;
A focusing step of focusing the image to be projected on the projection plane,
The focusing step includes
It is determined whether or not the measurement positions are on the same plane from the measurement results of the measurement positions obtained by the ranging step. If the measurement positions are not on the same plane, the measurement results of the measurement positions are determined. A projection method characterized in that a virtual plane is calculated based on and the image to be projected is focused on the virtual plane. A projecting step for projecting an image onto a projection surface;
A ranging step of measuring each distance to at least three measurement positions on the projection plane;
A focusing step of focusing the image to be projected on the projection plane,
The focusing step includes
It is determined whether or not the measurement positions are on the same plane from the measurement results of the measurement positions obtained by the ranging step. If the measurement positions are not on the same plane, the measurement results of the measurement positions are determined. A program that calculates a virtual plane based on the image and focuses the projected image on the virtual plane.

Images