JP2007334191A - Projection apparatus, range finding processing method, and program - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To perform range finding processing and focusing processing even in an over-exposure state once due to incident light of a phase difference sensor in the case the projection distance up to a screen is short or in the case of an excessively bright lamp. <P>SOLUTION: When judgment is made that there are measurement points at which the lightness at a plurality of the measurement points of a chart image projected onto a screen attain the maximum level, the lightness at the measurement points of the chart image stored in a video RAM 34 is partially corrected so as to be made lower than the maximum level. After the lightness at the measurement points of the chart image stored in the video RAM 34 is partially corrected so as to uniformize the lightness at each measurement point, the distance to each of the measurement points is measured and the focusing position of the projected chart image is variably controlled based on the distance data at each of the obtained measurement points. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a projection device that projects an arbitrary image on a screen, for example, a projection capable of performing ranging processing and focusing processing even when the exposure is once overexposed by incident light of a phase difference sensor. The present invention relates to a device, a distance measurement processing method, and a program.

  Conventionally, a projection apparatus projects light onto a screen and forms an image on the screen. By the way, when the optical axis of the projection light is not incident on the screen perpendicularly, distortion occurs in which the image on the screen has a trapezoidal shape. For this reason, the projection apparatus corrects such image distortion by detecting the tilt angle of the screen with respect to the optical axis.

Further, the conventional projection apparatus is configured such that the projection lens system can be electrically driven, and zoom control and focus control are possible. In order to realize an AF (Auto Focus) function, a chart image for distance measurement is projected on the screen, and distances corresponding to a plurality of measurement points on the screen are obtained by phase difference sensors arranged orthogonal to each other. Each is measured (for example, refer to Patent Document 1).
JP 2005-6228 A

  However, when a chart image for distance measurement is projected on the screen, the entire screen of the image is not always displayed with the same brightness. For example, when the optical axis of the projection apparatus is tilted with respect to the screen, a portion near the projection lens is bright and a portion far from the projection lens is darkly displayed on the screen.

  In this way, if the brightness of the image screen is partially different, the phase difference sensor cannot accurately detect each measurement point (white part) on the image screen, causing erroneous distance measurement, etc. May be reduced.

  In addition, if the power of the lamp as the light source is large and the projection image is too bright, or if the projection distance between the screen and the projection device is short, the phase difference sensor will overexpose before reaching the integration time for exposure. It becomes a state. A so-called halation phenomenon occurs. For this reason, when the output signal from the phase difference sensor is A / D converted, the maximum level value of the resolution is obtained, and effective sensor output data cannot be obtained.

  As described above, when the lamp is too bright or the projection distance to the screen is short, there is a problem that AF control cannot be performed. In view of this, there has been a demand for a method of controlling so as to project a chart image having optimum brightness even when the exposure is once overexposed by the incident light of the phase difference sensor.

  The present invention has been made in view of the above, and as its purpose, when the lamp is too bright or when the projection distance to the screen is short, the light is once overexposed by the incident light of the phase difference sensor. However, an object of the present invention is to provide a projection apparatus, a distance measurement processing method, and a program capable of performing distance measurement processing and focusing processing.

  (1) The present invention relates to a storage means for storing a chart image, a projection means for reading out and projecting the chart image from the storage means, and brightness at a plurality of measurement points of the chart image projected on the screen by the projection means. Brightness detection means for detecting the brightness at a predetermined resolution, judgment means for judging whether the brightness at each measurement point detected by the brightness detection means is the maximum level of resolution of the brightness detection means, and this judgment means Illuminance correction means for correcting the illuminance at the corresponding measurement point of the chart image stored in the storage means so as to be lower than the maximum level when it is determined that there is a measurement point having the maximum level of resolution. And the illuminance at the measurement points of the chart image stored in the storage means are corrected so that the brightness at each measurement point detected by the brightness detection means is uniform. Based on the uniformization correction means, the distance measurement means for measuring the distance to each measurement point after being corrected by the uniformization correction means, and the projection based on the distance data of each measurement point obtained by the distance measurement means Focusing control means for variably controlling the focus position of the chart image projected by the means.

  (2) The present invention is a distance measurement processing method used in a projection apparatus including a storage unit that stores a chart image and a projection unit that reads and projects the chart image from the storage unit. A brightness detection step that detects the brightness at a plurality of measurement points of the chart image projected on the screen with a predetermined resolution, and the brightness at each measurement point detected by this brightness detection step is the maximum level of resolution of this brightness detection step. A determination step for determining whether or not the measurement point is determined, and when it is determined that there is a measurement point having the maximum level of the resolution, the storage unit stores the determination unit so as to be lower than the maximum level. The illuminance correction step for correcting the illuminance at the corresponding measurement point of the chart image and the brightness at each measurement point detected by this brightness detection step are made uniform. A uniform correction step for correcting the illuminance at the measurement point of the chart image stored in the storage unit, a distance measurement step for measuring the distance to each measurement point after correction by the uniform correction step, And a focus control step of variably controlling the focus position of the chart image projected by the projection device based on the distance data of each measurement point obtained by the distance measurement step.

  (3) The present invention is a program executed by a computer built in a projection apparatus that includes a storage unit that stores a chart image and a projection unit that reads out and projects the chart image from the storage unit. A brightness detection step for detecting the brightness at a plurality of measurement points of the chart image projected on the screen by the unit at a predetermined resolution, and the brightness at each measurement point detected by the brightness detection step is the resolution of the brightness detection step. A determination step for determining whether or not the level is the maximum level, and when the determination step determines that there is a measurement point that has the maximum level of the resolution, the storage unit stores the level so as to be lower than the maximum level. The illuminance correction step for correcting the illuminance at the corresponding measurement point of the chart image being read, and at each measurement point detected by this brightness detection step A uniform correction step for correcting the illuminance at the measurement points of the chart image stored in the storage unit so that the brightness is uniform, and after the correction by the uniform correction step, the distance to each measurement point is measured. A computer executes a distance measurement step and a focus control step for variably controlling a focus position of a chart image projected by the projection device based on distance data of each measurement point obtained by the distance measurement step. It is characterized by that.

  According to the present invention, when the brightness of the chart image projected on the screen is detected at a predetermined resolution and reaches the maximum level, the illuminance at the measurement point of the chart image is partially corrected, and the brightness at each measurement point is corrected. If the lamp is too bright or the projection distance to the screen is short, even if the overexposure is once caused by the incident light of the phase difference sensor, Focusing processing can be performed.

  Embodiments of the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram showing an external configuration when a small projector device is taken as an example of a projection device according to an embodiment of the present invention, and FIG. 1 (A) is a perspective view when viewed from above, B) is a perspective view when viewed from below.

  As shown in FIG. 1A, the projector device 10 is provided with a projection lens 12, two phase difference sensors 131 and 132, and an Ir receiver 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 light modulation element such as a micromirror element to be described later. In this embodiment, the in-focus position and the zoom position (projection angle of view) are arbitrarily set. It shall be variable.

  The phase difference sensors 131 and 132 measure the distance to the subject, specifically, the distance to the image on the screen, based on the principle of triangulation from the parallax with respect to the subject image. Specifically, the distance to the subject in the vertical direction (vertical direction) is measured by the distance measuring lenses 13 a and 13 b of the phase difference sensor 131 arranged in the vertical direction with respect to the main body casing 11. The distance measuring lenses 13c and 13d of the phase difference sensor 132 arranged in the horizontal direction are configured to measure the distance to the subject in the horizontal direction (horizontal direction).

  The Ir receiver 14 receives infrared light on which key operation signals from a remote controller (not shown) of the projector device 10 (not shown) are superimposed.

  A main body main key / indicator 15, a speaker 16, and a cover 17 are disposed on the upper surface of the main body casing 11. Details of the main body main key / indicator 15 will be described later. The speaker 16 amplifies and outputs sound when playing back a moving image. Here, the cover 17 opens and closes when a subkey (not shown) is operated. This sub key is operated to instruct to set various detailed operations and the like that cannot be set with the main unit key / indicator 15 key without using the remote controller of the projector apparatus 10.

  Further, as shown in FIG. 1B, an input / output connector portion 18, an Ir receiving portion 19, and an AC adapter connecting portion 20 are disposed on the back surface of the main body casing 11.

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

  Similar to the Ir receiver 14, the Ir receiver 19 receives infrared light on which a key operation signal from a remote controller (not shown) is superimposed. The AC adapter connection unit 20 connects a cable from an AC adapter (not shown) serving as a power source.

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

  FIG. 2 is a diagram showing a detailed arrangement of the main body main key / indicator 15.

  The main body main key / 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 15g,“ Keystone ”key 15h,“ HELP ”key 15i,“ Esc ”key 15j,“ Up (↑) ”key 15k,“ Down (↓) ”key 15l,“ Left (←) ”key 15m,“ It includes a “write (→)” key 15n, an “enter” key 15o, a power / standby indicator 15p, and a temperature (TEMP) indicator 15q.

  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 automatic focusing and automatic keystone correction.

  The “Input” key 15 e instructs manual switching of the video signal input to any of the input / output connector sections 18, and the “Auto” key 15 f is a video signal input to any of the input / output connector sections 18. Directs automatic switching.

  The “menu” key 15g instructs display of various menu items relating to the projection operation, and the “Keystone” key 15h instructs manual operation of keystone correction. 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, “down” key 15l, “left” key 15m, and “right” key 15n are used to indicate a menu item, manual keystone correction direction, pointer, cursor, or the like at that time to select or move. Operate accordingly.

  The power / standby indicator 15p displays a power on / off state and a state in which no video 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.

  FIG. 3 is a block diagram showing a functional configuration of the electronic circuit of the projector apparatus 10. In FIG. 3, for example, when a video signal composed of analog signals of RGB specifications is input from the input / output connector unit 18, video A / D converters 31a, 31b, 31c provided in the input / output interface (I / F) 31 are provided. A / D conversion is performed and the scaler unit 32 outputs the result. The scaler unit 32 unifies the video data in a predetermined format so that the image data matches the resolution of the display element 36, and then outputs the video signal to the display controller unit 33.

  Note that video signals of various standards input from the input / output connector unit 18 are unified into video signals of a predetermined format by the scaler unit 32 via the input / output interface (I / F) unit 31 and the system bus SB. It is sent to the display controller unit 33.

  The display controller unit 33 develops and stores the image data input from the scaler unit 32 and the controller unit 39 in the video RAM unit 34, and generates a video signal from the stored contents of the video RAM unit 34.

  In this display controller unit 33, image data stored in the video RAM 34 is read out at an appropriate frame rate to generate a video signal, and this video signal is output from the spatial light modulation element (SOM) at, for example, 30 [frames / second]. The display element 36 is driven for display. For example, the display element 36 is irradiated with high-intensity white light emitted from a light source lamp 37 such as an ultra-high pressure mercury lamp, so that reflected light from the display element 36 is projected onto the screen 56 via the projection lens 12. Thus, a light image is formed and displayed. The projection lens 12 is driven by a lens motor (not shown) controlled by the zoom / focus control unit 38 so as to appropriately move the zoom position and the focus position.

  The controller unit 39 is composed of a microcomputer, and executes an operation program read from a ROM that stores an operation program including an automatic focusing process and an automatic trapezoid correction process, which will be described later, and a RAM that is used as a work memory and ROM. CPU and the like. The controller unit 39 controls all the operations of each circuit. The controller unit 39 is connected to an image storage unit 40, an audio processing unit 41, and a sensor control unit 42 via a system bus SB.

  The image storage unit 40 includes, for example, a flash memory, and stores image data of a chart image (horizontal chart image and vertical chart image) described later and a user logo image. The controller unit 39 appropriately reads the instructed image data from the image storage unit 40 and stores it in the video RAM unit 34 via the display controller unit 33.

  The sound processing unit 41 includes a sound source circuit such as a PCM sound source, generates sound signals by analogizing sound data given during the projection display operation, and drives the speaker 16 to emit loud sounds.

  The sensor control unit 42 outputs sensor integration control signals S1 and S3 to the phase difference sensor 131 having the distance measurement lenses 13a and 13b and the phase difference sensor 132 having the distance measurement lenses 13c and 13d to drive these sensors. The sensor output signals S2 and S4 output from the phase difference sensors 131 and 132 are input. The sensor control unit 42 includes an A / D converter 42a having a resolution of, for example, 8 bits for converting the sensor output signals S2 and S4 into digital signals, and this sensor output data is stored in a RAM provided in the controller unit 39. Output. The controller unit 39, which stores sensor output data from the sensor control unit 42 in the RAM, measures the distance to an arbitrary point position in a projected and displayed chart image to be described later.

  The CW (Color Wheel) control unit 44 is controlled according to the synchronization signal S5 output from the display controller unit 33, and generates a color wheel motor drive signal S6 synchronized with the vertical synchronization signal of the synchronization signal S5 (not shown). ) To rotate the color wheel 45.

  The color wheel 45 is a circular light transmission plate, and transmits one color of white light emitted from the light source lamp 37 by a transmission plate divided into four colors of W, R, G, and B. A marker portion (not shown) is provided on the outer periphery of the color wheel 45. When the color wheel 45 rotates and the marker portion passes over a photocoupler (not shown), the rotation is performed once. A marker signal S7 composed of a high-level pulse generated once is output to the CW control unit 44.

  The light transmitted through the color wheel 45 is emitted in the direction of the mirror 48 via the integrator 47, and the light reflected by the reflection surface of the mirror 48 is reflected by each pixel of the display element 36, and further from each pixel. The light reflected in the optical axis direction is projected on the screen 56 via the projection lens 12.

  The main body main key / indicator 15 and the main body subkey provided in the cover 17 constitute a key / indicator unit 43, and a key operation signal in the key / indicator unit 43 is directly input to the controller unit 39, and the controller The unit 39 directly lights / flashes the power / standby indicator 15p and the temperature indicator 15q, while the infrared light reception signals received by the Ir receiver unit 14 and the Ir receiver unit 19 are also directly input to the controller unit 39. .

  Next, an angle detection method using the phase difference sensor method used in the projector apparatus 10 will be described with reference to FIGS. Here, of the two sets of phase difference sensors 131 and 132 provided in the projector device 10, the phase difference sensor 132 for horizontal distance measurement will be described as an example. The same applies to the phase difference sensor 131 for vertical distance measurement.

  First, the principle of triangulation will be described with reference to FIG.

  FIG. 4 is an explanatory diagram showing a case where the phase difference sensor 132 used for horizontal distance measurement is viewed from above. The phase difference sensor 132 includes a pair of distance measuring lenses 13c and 13d and a pair of photo sensor arrays 51 and 52 disposed to face the distance measuring lenses 13c and 13d.

  Now, when measuring the distance from the phase difference sensor 132 to the subject 53 projected on the screen, the reflected light of the light emitted to the subject 53 is coupled to the photosensor array 51 through one distance measuring lens 13c. The reflected light is imaged on the photosensor array 52 through the other distance measuring lens 13d. 54 and 55 in the figure show the subject images.

Here, the distances between the optical axes of the distance measuring lenses 13c and 13d and the imaging are respectively x1 and x2, the distance between the optical axes of the distance measuring lenses 13c and 13d is B, and the distance between the photosensor arrays 51 and 52 and the distance measurement. Assuming that the distance between the lenses 13c and 13d is f, the distance d to the subject 53 can be obtained by the following equation.
d = B * f / (x1 + x2) (1)

  In equation (1), B and f are values specific to the sensor, and therefore the distance d to the subject 53 is obtained by the phase (x1, x2) of the photosensor arrays 51 and 52.

  Next, multipoint ranging will be described with reference to FIGS.

  FIG. 5 is an explanatory diagram of the phase difference sensor 132. Each of the pair of photosensor arrays 51 and 52 includes 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 ranging is performed for each group.

  In the example shown in FIG. 5, the photosensors included in the photosensor arrays 51 and 52 are divided into three groups, and the right side is measured toward the screen 56 using the photosensors of the A1 and A2 groups. A case is shown in which the vicinity of the center of the screen 56 is measured using the photo sensor of the B2 group and the left side is measured toward the screen 56 using the photo sensors of the C1 and C2 groups.

  Here, in FIG. 6, the positional relationship between the phase difference sensor 132 and the screen 56 is shown. When the phase difference sensor 132 and the screen 56 are parallel, three measurement points on the right side, the center, and the left side of the screen 56 are shown. When the distance is measured (D, E, F), the relationship that the phase difference is D = E = F is established.

  On the other hand, when the screen 56 is tilted by θ and is in the state 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 D ′ <E ′ <F ′. In this case, since the screen 56 is a plane, these three points can be expressed as a linear straight line. 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.

  By the way, when the distance measurement as described above is performed, a chart image composed of a black and white pattern image as shown in FIGS. 7A and 7B so that each measurement point can be detected by the phase difference sensors 131 and 132. 61, 71 are used.

  FIG. 7A is a diagram showing an example of a horizontal chart image 61 used for horizontal distance measurement. In this horizontal chart image 61, patterns of three white lines 62 to 64 are equally spaced in the vertical direction. Has been placed. The portions other than the white lines 62 to 64 are black (dark portions), whereas the portions of the white lines 62 to 64 are white (bright portions), and the pattern of the image 61 is subjected to a phase difference sensor in the horizontal direction from the difference in contrast. When read at 132, three measurement points P1, P2, P3 can be detected.

  FIG. 7B is a diagram showing an example of the vertical chart image 71 used for vertical distance measurement, which is the same as the one in which the direction of the horizontal chart image 61 is changed. That is, in the vertical chart image 71, patterns of three white lines 72 to 74 are arranged at equal intervals in the horizontal direction. The portions other than the white lines 72 to 74 are black (dark portions), while the portions of the white lines 72 to 74 are white (bright portions), and the pattern of the image 61 in the vertical direction is detected from the difference in contrast. When read by 131, three measurement points P4, P5 and P6 can be detected.

  Here, when the horizontal chart image 61 shown in FIG. 7A is projected onto the screen 56 and the measurement points P1, P2, and P3 are measured by the phase difference sensor 132, the entire screen of the horizontal chart image 61 is displayed. Is required to have uniform brightness. This is because the phase difference sensor 132 detects the measurement points P1, P2, and P3 according to the reflected light from the screen, so that if the screen brightness is uneven, all of the measurement points P1, P2, and P3 are detected. This is because it may not be detected accurately and may cause erroneous distance measurement.

  The same applies to the case where the vertical chart image 71 shown in FIG. 7B is projected on the screen 56 and the phase difference sensor 131 measures the measurement points P4, P5, and P6.

  Such variation in brightness occurs particularly when the projector apparatus 10 is installed inclined with respect to the screen 56 as shown in FIG. That is, in the example shown in FIG. 8, the portion of the white line 64 close to the projection lens 12 of the projector device 10 is brightest, followed by the white line 63 and the white line 62 in this order.

  In such a case, it is usually necessary for the user to adjust the projector device 10 so that the white lines 62 to 64 are displayed with the same brightness by correcting the tilt of the projector device 10. In the present embodiment, this is automatically adjusted. Then, the brightness of the brightest part on the screen 56 is limited, and the distance measurement is executed after the brightness of each part is made uniform.

  Hereinafter, the operation of the present embodiment will be described in detail with reference to FIGS. 9 to 12.

  FIG. 9 shows the processing contents of automatic focusing and automatic keystone correction as interrupt processing that is forcibly executed by operating the “AFK” key 15d of the main body main key / indicator 15 in a state where the power is on. It is a flowchart, and is controlled by a CPU provided in the controller unit 39 reading out operation programs stored in the ROM and sequentially executing them.

  Here, in response to the operation of the “AFK” key 15d, the one-shot mode in which the automatic focusing process and the automatic trapezoidal correction process are executed only once, and again after the “AFK” key 15d is operated for the first time, 2 Until the second operation, either the automatic focusing process or the continuous mode in which the automatic trapezoidal correction process is repeatedly and continuously executed is previously set to the “menu” key 15 g of the main body main key / indicator 15 and the “up” key. It is assumed that the user arbitrarily switches and sets by operating the “key” 15k, the “down” key 15l, the “Enter” key 15o, and the like.

  At the beginning of the process, the operation waits until the “AFK” key 15d is operated (step A10). When it is determined that the “AFK” key 15d is operated, the operation up to that point is interrupted and interrupt processing is performed. First, the first automatic focusing process and the automatic keystone correction process are executed (step A30).

  FIG. 10 is a subroutine showing the contents of the automatic focusing process and the automatic trapezoidal correction process. Initially, the image of the horizontal chart image 61 stored in the image storage unit 40 by the projection system including the projection lens 12 is shown. Data is read out, the image data is transferred from the scaler unit 32 to the video RAM 34 via the display controller unit 33, and the image data of the horizontal chart image 61 is stored in the video RAM 34, as shown in FIG. The horizontal chart image 61 is projected and displayed (step B10). The horizontal chart image 61 is composed of a pattern image having three white lines 62 to 64 arranged in the horizontal direction at equal intervals.

  In a state where the horizontal chart image 61 is projected and displayed on the screen 56, first, the sensor control unit 42 outputs and drives the sensor integration control signal S3 to the horizontal distance measuring phase difference sensor 132, and the phase difference sensor 132 is driven. Is output to the A / D converter 42a, and sensor output data output from the A / D converter 42a is stored in the RAM provided in the controller unit 39, so that the horizontal direction is obtained. The measurement points P1, P2, P3 (bright points) on the white lines 62 to 64 are sequentially read (step B20), and the brightness of these measurement points P1, P2, P3 is detected (step B30).

  Here, when the brightness of at least one of the measurement points P1, P2, and P3 is FFh, the brightness is higher than the dynamic range of the A / D converter 42a. That is, since the overexposure state is reached before reaching the integration time for exposing the phase difference sensor (Yes in Step B40), the horizontal chart image 61 corresponding to the measurement point where the brightness is FFh. Image data is read from the video RAM 34, and 01h is subtracted from this data and written to the video RAM 34 again to correct the illuminance to partially decrease (step B50).

  A specific example is shown in FIG. As shown in FIG. 11A, as a result of reading the measurement points P1, P2, and P3 on the white lines 62 to 64 in the horizontal chart image 61, as shown in FIG. 11B, P1 <P2 It is assumed that the brightness differs in the order of <P3, and the brightness at the measurement point P3 is the maximum brightness value (FFh) output from the A / D converter 42a. In this case, when the lamp is too bright or the projection distance to the screen is short, a halation phenomenon may occur at the measurement point P3, resulting in high brightness exceeding the dynamic range of the A / D converter 42a. ing.

  In such a case, as shown in FIG. 11C, with respect to the brightness of the measurement point P3, the brightness of the measurement point P3 is, for example, FEh (not shown in FIG. 11C) within the dynamic range. As described above, the illuminance data of the pixel portion corresponding to the measurement point P3 in the horizontal chart image 61 stored in the video RAM 34 is decreased by 01h and stored again in the video RAM 34. Then, returning to step B10, the corrected horizontal chart image 61 is projected and displayed on the screen 56 by the display element. At this time, the brightness of the measurement points P1 and P2 is not changed.

  Further, when the lamp is too bright or when the projection distance to the screen is short, the projector device 10 is not provided when the projector device 10 is inclined with respect to the screen 56 as shown in FIG. When 10 is installed, the brightness of the measurement points P1, P2, and P3 may be set to the maximum value (FFh). In this case, all the brightness values of the measurement points P1, P2, and P3 are decreased so as to be within the dynamic range.

  The horizontal chart image 61 is corrected for illuminance each time Steps B40 and B50 are executed once, and the brightness of the measurement points P1, P2 and P3 is rechecked. As a result, the brightness is determined to be FEh or less. In this case, the halation phenomenon can be suppressed because it falls within the dynamic range. That is, even if the integration time of the phase difference sensor is reached, the overexposure state does not occur (No in step B40). Next, when the brightness of the measurement points P1, P2, and P3 varies and is not uniform (No in Step B43), the measurement points P1, P2, and P3 have the same brightness. The illuminance at the measurement point of the horizontal chart image 61 is partially corrected (step B45).

  Specifically, by comparing the lightness (degrees of brightness) of the measurement points P1, P2, and P3, the lightness of the second brightest measurement point is used as a reference value, and the lightness of other measurement points is used as the reference. The image data of the horizontal chart image 61 stored in the video RAM 34 is corrected so as to approach the value.

  A specific example is shown in FIG. Now, as shown in FIG. 12A, as a result of reading the measurement points P1, P2, and P3 on the white lines 62 to 64 in the horizontal chart image 61, as shown in FIG. 12B, P1 <P2 It is assumed that the brightness differs in the order of <P3.

  In such a case, as shown in FIG. 5C, the other measurement points P1 and P3 are corrected in accordance with the lightness of the second brightest measurement point P2. Regarding the brightness of the measurement point P1 portion, the illuminance of the pixel portion of the projection image corresponding to the measurement point P1 in the horizontal chart image 61 is calculated based on the difference between the brightness of the measurement point P1 and the brightness of the measurement point P2 serving as a reference. In order to increase, the image data of the horizontal chart image 61 stored in the video RAM 34 is corrected.

  Similarly, regarding the brightness of the measurement point P3, the pixel portion of the projection image corresponding to the measurement point P3 in the horizontal chart image 61 is based on the difference between the brightness of the measurement point P3 and the brightness of the reference measurement point P2. Image data of the horizontal chart image 61 stored in the video RAM 34 is corrected.

  When the brightness of the measurement points P1, P2, P3 is re-detected after the illuminance correction, when it is determined that each of the measurement points P1, P2, P3 has the same brightness and is uniform (Yes in step B43), The sensor control unit 42 sequentially measures the distances to the projection image positions of the measurement points P1, P2, and P3 of the horizontal chart image 61 (step B60).

  Note that the order of measuring each measurement point is not particularly limited. For example, after measuring the measurement point P2 as the central point first, the measurement point P1 as the left point toward the screen, and the screen Alternatively, the measurement may be performed in the order of the measurement point P3 that becomes the right point toward. The distance data of each measurement point obtained here is stored and held in a distance measurement result storage unit 39 a provided in the controller unit 39.

  Here, an angle “θh” in the horizontal direction (horizontal direction) on the screen with respect to the projection optical axis is calculated based on the distance data of the measurement points P1, P2, and P3 stored in the distance measurement result storage unit 39a ( Step B70).

  Next, instead of the horizontal chart image 61, the vertical chart image 71 shown in FIG. 7B is projected and displayed based on the image data stored in the image storage unit 40 (step B80). The vertical chart image 71 includes a pattern image having three white lines 72 to 74 arranged in the vertical direction at equal intervals.

  In a state where the vertical chart image 71 is projected and displayed, first, the phase difference sensor 131 for vertical distance measurement is driven, and the measurement points P4, P5 and P6 (bright points) on the white lines 72 to 74 are sequentially arranged in the vertical direction. By reading (step B90), the brightness of these measurement points P4, P5, and P6 is detected (step B100).

  Here, when the brightness of at least one of the measurement points P4, P5, and P6 is FFh (Yes in Step B110), the illuminance of the projection image corresponding to the measurement point with the brightness of FFh is partially set. So as to decrease automatically (step B120).

  When the brightness of the measurement points P4, P5, and P6 is rechecked after the illuminance correction, if it is determined that the brightness is FEh or less, the halation phenomenon occurs because the brightness is within the dynamic range. It was able to be suppressed. That is, even if the integration time of the phase difference sensor is reached, the overexposure state is not reached (No in step B110). Next, when the brightness of the measurement points P4, P5 and P6 varies and is not uniform (No in Step B113), a horizontal chart is used so that these measurement points P4, P5 and P6 have the same brightness. The illuminance of the projection image is partially corrected by the same method as that for the image 61 (step B115).

  If the brightness of the measurement points P4, P5, and P6 is rechecked after the illuminance correction, and it is determined that each has the same brightness and is uniform (Yes in step B113), the sensor The controller 42 sequentially measures the distances of the measurement points P4, P5, and P6 of the vertical chart image 71 to the respective projection image positions (step B130).

  Note that the order of measuring each measurement point is not particularly limited. For example, after measuring the measurement point P5 as the central point first, the measurement point P4 as the upper point toward the screen, and the screen Alternatively, the measurement may be performed in the order of the measurement point P6 that becomes the lower point toward. The distance data of each measurement point obtained here is stored and held in a distance measurement result storage unit 39 a provided in the controller unit 39.

  Here, based on the distance data of the measurement points P4, P5, and P6 stored in the distance measurement result storage unit 39a, an angle “θv” in the vertical direction on the screen with respect to the projection optical axis is calculated ( Step B140).

  Next, the distance to the projection image position of the measurement point located at the center measured in step B20 or B90 is obtained as it is as a distance value representative of the projection image (step B150), and the distance corresponding to the distance value is obtained. The projection lens 12 is moved by controlling a lens motor (not shown) by the zoom / focus control unit 38 so as to be in the focal position.

  After that, based on the horizontal angle “θh” and the vertical angle “θv” on the screen on which the image obtained in Steps B70 and B140 is projected, what angle and in what direction the screen is overall Whether the projection image should be a rectangle with the same appropriate aspect ratio as the input video signal, the required trapezoidal correction angle is calculated and stored in the display controller 33 by the video RAM 34. After setting the ratio of the upper side to the lower side and the ratio of the left side to the right side of the image data to be corrected (step B160), the series of subroutines shown in FIG. 10 is temporarily terminated and the process returns to the process shown in FIG. .

  In FIG. 9, after the automatic focusing and automatic keystone correction in step A30, it is determined whether or not the above-described continue mode is set at that time (step A40).

  Here, if it is determined that the continue mode is set, after confirming that there is no second operation of the “AFK” key 15d (step A50), the process returns to step A30, and automatic focusing and automatic are performed again. Perform keystone correction.

  In the state in which the continue mode is set in this way, the processes of steps A30 to A50 are repeatedly executed until the second “AFK” key 15d is operated, thereby continuously executing the processes of automatic focusing and automatic keystone correction. .

  If it is determined in step A50 that the second “AFK” key 15d has been operated, or if it is determined in step A40 that the one-shot mode is set instead of the continue mode, the automatic interrupt processing is performed at that time. A state for ending focusing and automatic keystone correction is set (step A60), and after returning to the previous operation, the process returns to step A10 in preparation for the operation of the “AFK” key 15d again.

  As described above, when the user operates the “AFK” key 15d of the main body main key / indicator 15, the distances to a plurality of measurement points corresponding to the vertical and horizontal directions in the screen are measured in response to the key operation. Based on the measurement result, automatic focusing of the projection image and automatic keystone correction are performed simultaneously. Therefore, it is possible to automatically adjust the in-focus position and the trapezoidal distortion of the projected image more easily and quickly with a single key instruction operation.

  In addition, when performing distance measurement, which is necessary as preprocessing for automatic focusing and automatic keystone correction processing, the distance is measured after automatically adjusting to the same brightness at each measurement point on the image screen. Thus, for example, even if the projector apparatus 10 is installed with an inclination with respect to the screen 56 as shown in FIG. 8, accurate distance data for each measurement point can be obtained, and automatic focusing using the distance data is possible. By the processing and the automatic keystone correction processing, it becomes possible to project a clean image without distortion on the screen.

  Further, when the brightness of the chart image projected on the screen is detected at a predetermined resolution and reaches the maximum level, the illuminance at the measurement point of the chart image is partially corrected, and the brightness at each measurement point is made uniform. Thus, for example, when the lamp is too bright or the projection distance to the screen is short, even if the exposure is once overexposed by the incident light of the phase difference sensor, the ranging process and the focusing process are performed. It can be carried out.

  If it is determined that there is a measurement point having the maximum level of resolution, the illuminance at the corresponding measurement point of the chart image stored in the video RAM is partially corrected until the measurement point becomes lower than the maximum level. By controlling so, the halation phenomenon can be suppressed.

  In addition, after suppressing the halation phenomenon, control is performed to correct the illuminance at the measurement points of the chart image stored in the video RAM until the brightness at each measurement point becomes uniform, thereby more accurately measuring the distance. And focusing processing can be performed.

  In addition, after suppressing the halation phenomenon, by partially correcting the illuminance at the measurement points of the chart image so that the brightness of the other measurement points is matched with the second brightest lightness at each measurement point as a reference Thus, the ranging process and the focusing process can be performed more accurately and quickly.

  In the embodiment, the distance is measured by determining three measurement points for each of the horizontal direction and the vertical direction of the image screen. However, the number of measurement points may be further increased. Similarly, the distance is measured after adjusting the brightness of the measurement point.

  Further, distance measurement may be performed by adjusting the brightness of each measurement point only in one of the horizontal direction and the vertical direction of the image screen. In this case, since the accuracy of distance measurement is generally required in the horizontal direction of the image screen, it is preferable to perform distance measurement by adjusting the brightness of each measurement point at least in the horizontal direction.

  In the embodiment, when adjusting the brightness of each measurement point, the brightness of the other measurement point is adjusted to the brightness of the darkest measurement point. However, the brightness of the other measurement point is set to the brightness of the brightest measurement point. For example, an average value of brightness at each measurement point may be obtained and matched with the average value.

  Further, the corrected chart image obtained by correcting the illuminance may be stored in the image storage unit 40 so that it can be read out again. In this case, after the power of the projector apparatus 10 is turned off, distance measurement can be performed with the read chart image without correcting the chart image even in the same installation state. Further, a plurality of corrected chart images may be stored in the image storage unit 40 so that the user can select and read them.

  In addition, the present invention is not limited to the embodiment, and various modifications can be made without departing from the scope of the invention.

  Further, the embodiments include inventions at various stages, and various inventions can be extracted by appropriately combining a plurality of disclosed constituent elements. For example, even if some constituent elements are deleted from all the constituent elements shown in the embodiment, at least one of the problems described in the column of the problem to be solved by the invention can be solved, and described in the column of the effect of the invention. In a case where at least one of the obtained effects can be obtained, a configuration in which this configuration requirement is deleted can be extracted as an invention.

  In addition, the method described in the above-described embodiment is a program that can be executed by a computer, such as a magnetic disk (flexible disk, hard disk, etc.), an optical disk (CD-ROM, DVD-ROM, etc.), a semiconductor memory, etc. The program can be written on a medium and applied to various apparatuses, or the program itself can be transmitted through a transmission medium such as a network and applied to various apparatuses. A computer that implements this apparatus reads a program recorded on a recording medium or a program provided via a transmission medium, and performs the above-described processing by controlling operations by this program.

It is a figure which shows the external appearance structure at the time of taking a small projector apparatus as an example as a projection apparatus which concerns on one Embodiment of this invention. It is a figure which shows the arrangement configuration of the main body main key / indicator provided in the projector apparatus of this embodiment. It is a block diagram which shows the function structure of the electronic circuit of the projector apparatus of this embodiment. It is a figure for demonstrating the principle of the triangulation of this embodiment. It is a figure for demonstrating the multipoint ranging of this embodiment. It is a figure which shows the positional relationship of the phase difference sensor of this embodiment, and a screen. It is a figure for demonstrating the chart image used at the time of ranging of the projector apparatus of this embodiment, (A) is a figure which shows an example of the horizontal chart image used for horizontal ranging, and the figure (B) is vertical. It is a figure which shows an example of the vertical chart image used for ranging. It is a figure which shows the relationship between the brightness of each measurement point in the chart image for ranging of this embodiment, and the inclination of a projector apparatus. It is a flowchart which shows the processing content with respect to AFK key operation of the projector apparatus of this embodiment. It is a flowchart which shows the processing content of the subroutine of the AFK process of the projector apparatus of this embodiment. It is a figure for demonstrating the correction method when the brightness of a measurement point becomes FFh by the projector apparatus of this embodiment. It is a figure for demonstrating equalizing and correcting the brightness of each measurement point with the projector apparatus of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Projector apparatus, 11 ... Main body casing, 12 ... Projection lens, 13a, 13b, 13c, 13d ... Distance measuring lens, 14 ... Ir receiver, 15 ... Main body main key / indicator, 15a ... Power key, 15b ... Zoom key, 15c ... Focus key, 15d ... "AFK" key, 15e ... "Input" key, 15f ... "Auto" key, 15p ... Power / standby indicator, 15q ... Temperature indicator, 16 ... Speaker, 17 ... Cover, 18 ... Input / output connector, 19 ... Ir receiver, 20 ... AC adapter connection, 21a, 21b ... Fixed leg, 22 ... Adjustment leg, 31 ... Input / output interface (I / F) 32 ... Scaler unit, 33 ... Display controller unit, 34 ... Video RAM, 35 ... Display drive unit, 36 ... Indicator element 37 ... Light source lamp 38 ... Lens motor (M) 39 ... Controller 39a ... Distance measurement result storage 40 ... Image storage 41 ... Audio processing part 42 ... Sensor control part 43 ... Key / Indicator section, SB ... system bus, 51, 52 ... photo sensor array, 54, 55 ... subject image, 56 ... screen, 61 ... horizontal chart image, 62-64 ... white line, P1-3 ... measurement point, 71 ... vertical chart Image, 72-74 ... white line, P4-6 ... measurement point, 131, 132 ... phase difference sensor.

Claims (6)

Storage means for storing a chart image;
Projection means for reading out and projecting the chart image from the storage means;
Brightness detection means for detecting the brightness at a plurality of measurement points of the chart image projected on the screen by the projection means with a predetermined resolution;
Determination means for determining whether or not the lightness at each measurement point detected by the lightness detection means is the maximum level of resolution of the lightness detection means;
When it is determined by the determination means that there is a measurement point having the maximum level of the resolution, the illuminance at the corresponding measurement point of the chart image stored in the storage means is corrected so as to be lower than the maximum level. Illumination correction means;
Uniformity correction means for correcting the illuminance at the measurement points of the chart image stored in the storage means so that the lightness at each measurement point detected by the lightness detection means is uniformized;
A distance measuring means for measuring the distance to each measurement point after being corrected by the uniformizing correction means,
A projection apparatus comprising: focus control means for variably controlling a focus position of a chart image projected by the projection means based on distance data of each measurement point obtained by the distance measurement means .   When the determination means determines that there is a measurement point that has the maximum level of the resolution, the illuminance at the corresponding measurement point of the chart image stored in the storage means is partially increased until the measurement point becomes lower than the maximum level. The projection apparatus according to claim 1, further comprising a control unit that controls the illuminance correction unit so as to correct the illuminance.   Control means for controlling the uniformization correction means so as to correct the illuminance at the measurement points of the chart image stored in the storage means until the brightness at each measurement point detected by the brightness detection means is uniformized; The projection apparatus according to claim 1, further comprising: The uniformizing correction means includes:
Partially correcting the illuminance at the measurement points of the chart image so that the brightness of the other measurement points is matched based on the second brightest brightness among the brightness at each measurement point detected by the brightness detection means. The projection apparatus according to claim 1, wherein: A distance measurement processing method used in a projection apparatus including a storage unit that stores a chart image and a projection unit that reads and projects the chart image from the storage unit,
A brightness detection step for detecting brightness at a plurality of measurement points of the chart image projected on the screen by the projection unit with a predetermined resolution;
A determination step of determining whether or not the lightness at each measurement point detected by the lightness detection step is the maximum level of resolution of the lightness detection step;
When it is determined in this determination step that there is a measurement point having the maximum level of the resolution, the illuminance at the corresponding measurement point of the chart image stored in the storage unit is corrected so as to be lower than the maximum level. Illuminance correction step;
A homogenization correction step of correcting the illuminance at the measurement points of the chart image stored in the storage unit so that the lightness at each measurement point detected by the lightness detection step is uniform;
A distance measuring step for measuring the distance to each measurement point after being corrected by the uniformization correction step;
Ranging processing comprising: a focusing control step for variably controlling a focusing position of the chart image projected by the projection device based on distance data of each measurement point obtained by the ranging step Method. A program executed by a computer incorporated in a projection apparatus including a storage unit that stores a chart image and a projection unit that reads and projects the chart image from the storage unit,
A brightness detection step for detecting brightness at a plurality of measurement points of the chart image projected on the screen by the projection unit with a predetermined resolution;
A determination step of determining whether or not the lightness at each measurement point detected by the lightness detection step is the maximum level of resolution of the lightness detection step;
When it is determined in this determination step that there is a measurement point having the maximum level of the resolution, the illuminance at the corresponding measurement point of the chart image stored in the storage unit is corrected so as to be lower than the maximum level. Illuminance correction step;
A homogenization correction step of correcting the illuminance at the measurement points of the chart image stored in the storage unit so that the lightness at each measurement point detected by the lightness detection step is uniform;
A distance measuring step for measuring the distance to each measurement point after being corrected by the uniformization correction step;
A focusing control step for variably controlling a focusing position of a chart image projected by the projection device based on distance data of each measurement point obtained by the ranging step is performed by the computer. program.

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