JP2007171327A - Projector unit and multi-vision system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To correct dispersion of each light source due to aging at a real time, without causing troubles in an image projected on a screen. <P>SOLUTION: The projector unit constituting a multi-vision system includes: the light source; a light source sensor for measuring the intensity of light emitted from the light source; a luminance data acquiring means for acquiring luminance data corresponding to the measured intensity; and a parameter adjusting means for adjusting a parameter related to the luminance of the projected image based on the acquired luminance data. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a projector unit for projecting an image and a multi-vision system that displays a single screen using a plurality of projector units.

  Multi-vision systems that display a single screen using a plurality of projectors stacked in a matrix are widely known and put into practical use. In the multivision system, each projector is driven and controlled to display each of the divided areas of one screen. By combining all the divided areas, a single large screen display is realized.

For example, Patent Document 1 below discloses a multivision system including a plurality of liquid crystal projectors. In the multivision system disclosed here, for example, a sensor for measuring luminance information of projection light is mounted for each liquid crystal projector. In each liquid crystal projector, the sensor is movably installed so as to selectively enter or retract on the optical path of the projection light. These sensors are normally retracted from the optical path, but only enter the optical path when measuring the luminance information of the projection light. By measuring each luminance information and referring to the results, the variation of the light source over time (specifically, the decrease in luminance, chromaticity, etc.) among the plurality of liquid crystal projectors is corrected appropriately. That is, the variation in the brightness of the projected image between the liquid crystal projectors is removed. Thereby, a large screen display with uniform luminance is realized.
JP-A-10-90645

  However, in the multivision system disclosed in Patent Document 1, it is necessary to move the sensor on the optical path as described above when performing luminance correction. In this case, the shadow of the sensor is projected on the screen. For this reason, luminance correction cannot be performed while an image is played on the screen. The timing at which the luminance correction can be performed is limited to, for example, when the power is turned on or when a user instruction is given.

  In other words, the multivision system disclosed in Patent Document 1 cannot detect a change in the light source over time while an image is being played on the screen. Therefore, for example, when an image is continuously flowed for a long time, there is a possibility that a decrease in brightness or variation of each light source may appear remarkably between liquid crystal projectors.

  Therefore, in view of the above circumstances, the present invention provides a multi-vision system capable of correcting in real time a luminance variation of each light source over time without causing an obstacle to an image flowing on the screen, and the multi-vision system. It is an object to provide a projector unit suitable for a vision system.

  A projector unit according to an aspect of the present invention that solves the above-described problems constitutes a multivision system. The projector unit includes a light source, a light source sensor for measuring the intensity of light emitted from the light source, luminance data acquisition means for acquiring luminance data corresponding to the measured intensity, and the acquired luminance data. And a parameter adjusting unit that adjusts a parameter related to the brightness of the projected image based on the light source sensor. The light source sensor is installed outside the optical path.

  In the projector unit, a light source sensor may be installed so as to receive leakage light from the light source.

  The light source may have a lamp that emits light and a reflecting mirror that is formed so as to cover a part of the lamp. In this case, the light source sensor can be installed to receive light leaking from the reflecting mirror.

  The projector unit may further include a cooling unit for cooling the light source. In this case, the light source sensor can be installed at a position cooled by the cooling means.

  The projector unit includes a projection optical system that emits projection light, and a projection light sensor for measuring the intensity of the projection light. The projector unit is disposed outside the optical path and faces the projection optical system. It may be further provided with a sensor. Note that the projection light sensor may be installed so as to receive leakage light from the projection optical system.

  Here, when the brightness data acquisition unit holds a table in which the intensity measured by the light source sensor and the brightness data are associated, the projector unit is based on the intensity measured by the light source sensor and the projection light sensor. Table updating means for updating the table.

  The parameter related to the brightness of the projected image can be, for example, contrast or brightness.

  The projector unit may further include a liquid crystal panel for forming a projection image. In this case, the parameter adjusting means can adjust the transmittance of the liquid crystal panel.

  Further, a projector unit constituting a multi-vision system according to another aspect of the present invention that solves the above problems includes an intensity measurement sensor that measures the intensity of a component that does not contribute to the formation of a projected image, and a measured intensity. A luminance data acquisition unit that acquires corresponding luminance data and a parameter adjustment unit that adjusts parameters related to the luminance of the projected image based on the acquired luminance data are provided, and an intensity measurement sensor is installed outside the optical path. It is characterized by that.

  In addition, a multivision system according to an aspect of the present invention that solves the above problems includes a plurality of the projector units. This multi-vision system includes a luminance data comparison unit that compares luminance data acquired by the luminance data acquisition unit of each projector unit, and a reference that sets a projector unit that satisfies a predetermined condition based on the comparison result as a reference projector unit. It is characterized by comprising setting means and parameter adjustment control means for controlling each parameter adjustment means so that an image is projected with the same luminance as that of the reference projector unit in all projector units.

  The reference setting means can set the projector unit that projects an image with the lowest luminance as satisfying the predetermined condition.

  In addition, a multivision system according to another aspect of the present invention that solves the above problems includes a light source, a light source sensor that is installed outside the optical path and measures the intensity of light emitted from the light source, and the intensity. A first storage unit storing brightness data of a projected image on a screen corresponding to the parameter, a parameter adjusting unit capable of adjusting a parameter value related to the brightness of the projected image, and a screen corresponding to the parameter value. This is a multi-vision system including a plurality of projector units each having a second storage unit in which brightness data of a projected image is stored. The multi-vision system includes a first reading unit that reads the corresponding luminance data from each first storage unit with reference to the intensity measured by the light source sensor of each projector unit, and each read luminance data Brightness data comparison means for comparing, a reference setting means for setting, as a reference projector unit, a projector unit that projects an image with the lowest brightness based on the comparison result, and a second provided other than the reference projector unit. And a parameter adjustment control means for controlling each parameter adjustment means so that an image is projected at a brightness equivalent to that of the reference projector unit in all projector units with reference to the second storage unit. It is.

  Here, each projector unit is a projection optical system that emits projection light, and a projection light sensor for measuring the intensity of the projection light, and is installed outside the optical path and facing the projection optical system. And a first storage unit updating means for updating the first storage unit based on the intensities measured by the light source sensor and the projection light sensor. Further, it may be provided.

  When the projector unit and the multi-vision system of the present invention are adopted, it is possible to correct the variation of each light source over time in real time without causing any trouble in the image flowing on the screen. For this reason, even when, for example, the multivision system is used continuously for a long time, the brightness of the image projected on the screen is kept uniform.

  Hereinafter, the configuration and operation of a multivision system according to an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram schematically showing a configuration of a multivision system 10 of the present embodiment. The multivision system 10 includes a system control unit 100, projector units P _{1 to} P ₄ , and a screen S. Note that the multi-vision system 10 of the present embodiment is assumed to be a rear projection image display system. However, it is also possible to employ such a multi-vision system in a front projection type image display system.

The system control unit 100 performs overall control of the system. In other words, the system control unit 100 controls each of the _four projector units P _{1 to} P ₄ to project one screen onto the screen S.

The projector units P _{1 to} P ₄ are installed in a matrix, for example. In the present embodiment, two are installed vertically and two horizontally. The projector units P ₁ , P ₂ , P ₃ , P ₄ can project images onto the areas R ₁ , R ₂ , R ₃ , R ₄ of the screen S, respectively. Projection images of the projector units are adjacent to each other on the screen S without a gap, forming a single image. Note that the number and arrangement of the projector units can be freely changed according to the design, and are not limited to the adoption example of the present embodiment.

  Here, a process executed by the multivision system 10 that displays a large screen on the screen S based on a video signal received from an image signal processing apparatus (not shown) (for example, a video processor or a computer terminal). explain.

For example, when the system control unit 100 receives a video signal for one frame from the image signal processing apparatus, the system control unit 100 divides the video signal to each projector unit and sends it out. Specifically, each of the projector units P ₁ , P ₂ , P ₃ , and P ₄ is abbreviated as image information of the upper left area of the image of one frame (hereinafter, “upper left area image information”. Are also abbreviated in the same manner), lower left region image information, upper right region image information, and lower right region image information are transmitted.

Figure 2 is a block diagram showing a configuration of a projector unit P ₁ of the present embodiment. The projector units P _{2 to} P ₄ have the same configuration as the projector unit P ₁ . Further, it operates in the same manner as the projector unit P _{1 under} the control of the system control unit 100. Accordingly, the description of the configuration and operation of the projector units P _{2 to} P ₄ is omitted in the description of the configuration and operation of the projector unit P _{1 in} order to avoid duplication.

As shown in FIG. 2, the projector unit P <b> ₁ has a liquid crystal projector unit 200. First, the liquid crystal projector unit 200 will be described.

  FIG. 3 is a diagram schematically showing the configuration of the liquid crystal projector unit 200 of the present embodiment. As shown in FIG. 3, the liquid crystal projector unit 200 is a device on which a three-plate transmissive liquid crystal projector is mounted.

  The liquid crystal projector unit 200 has a light source 202. The light source 202 includes a known lamp 202a and a parabolic mirror 202b. The lamp 202a is, for example, an ultra-high pressure mercury lamp or a metal halide lamp, and a driving voltage is supplied from a power source (not shown) of the multi-vision system 10. The lamp 202a starts to emit light as soon as the power is turned on. After a few minutes, a stable amount of white light is output (in other words, the output is not stable until a few minutes have passed). This white light is converted into parallel light and emitted by the action of the parabolic mirror 202b.

  The lamp 202a emits extremely high heat. For this reason, there is a possibility that the temperature inside the liquid crystal projector unit 200 is remarkably increased. An internal temperature increase can cause each component to deteriorate (for example, a decrease in performance due to a shape change or a temperature characteristic). In order to avoid this, a cooling fan 226 is installed in the vicinity of the parabolic mirror 202b. Similarly to the lamp 202a, the fan 226 is supplied with a driving voltage when the power of the multi-vision system 10 is turned on. The cooling air is sent to the lamp 202a by operating with the supplied driving voltage. This cooling air cools the light source 202 and reduces the temperature rise inside the liquid crystal projector unit 200.

  The parallel light emitted from the light source 202 enters the illumination optical system 204. The illumination optical system 204 includes, for example, an integrator lens and a polarization conversion element. In order to reduce luminance unevenness in the projected image, the parallel light is converted into parallel light having a more uniform distribution by the action of the integrator lens. Further, the parallel light is aligned in a predetermined polarization state by a polarization conversion element in order to reduce a light amount loss in a liquid crystal panel described later. Next, the light enters the first dichroic mirror 206.

  The first dichroic mirror 206 is an element having wavelength selectivity and transmits only the B color component. Accordingly, only the B color component of the parallel light emitted from the illumination optical system 204 passes through the first dichroic mirror 206 and travels straight, and the remaining components (R and G color components) are reflected by the first dichroic mirror 206. The optical path can be bent 90 degrees.

  The component reflected by the first dichroic mirror 206 is incident on the second dichroic mirror 208. The second dichroic mirror 208 is also an element having wavelength selectivity, and transmits only the R color component. Accordingly, only the R color component of the components reflected by the first dichroic mirror 206 is transmitted through the second dichroic mirror 208 and travels straight, and the remaining component (G color component) is reflected by the second dichroic mirror 208. The optical path can be bent 90 degrees.

  The R color component transmitted through the second dichroic mirror 208 is bent 90 degrees by the reflection mirror 210 and enters the transmissive liquid crystal panel 218R. Further, the G color component reflected by the second dichroic mirror 208 is bent 90 degrees by the reflection mirror 212 and enters the transmissive liquid crystal panel 218G. Further, the B color component transmitted through the first dichroic mirror 206 is incident on the transmissive liquid crystal panel 218 </ b> B after the optical path is bent by the reflecting mirror 214 and the reflecting mirror 216. Note that the optical path lengths of these color components are all made equal by an optical element (not shown) and are incident on each transmissive liquid crystal panel at the same timing.

  Here, the liquid crystal projector unit 200 includes a projector control unit 230. The projector control unit 230 performs overall control of the unit. For example, when the upper left area image information is received from the system control unit 100, each transmissive liquid crystal panel is controlled based on the information. Thus, each color component is modulated by each transmissive liquid crystal panel and is incident on the combining prism 220. For simplification of the drawing, the connection between the projector control unit 230 and each transmissive liquid crystal panel is omitted in FIG.

The combining prism 220 combines the respective color components and outputs them to the projection optical system 222. The projection optical system 222 projects this combined light onto the area R _{1 of the} screen S.

The combined light is similarly projected on the liquid crystal projector units of the projector units P ₂ , P ₃ , and P ₄ . Thereby, each image is projected onto the areas R ₂ , R ₃ , and R ₄ of the screen S. Since the projected images in the regions R _{1 to} R ₄ form one image, one large screen display is realized on the screen S.

There are individual differences (for example, variations in effective luminous intensity of each light source, variations due to manufacturing errors, assembly errors, etc.) of the light sources and optical elements between the projector units. Therefore, for example, a brightness difference may occur in the projected images between the projector units. In such a case, the brightness in units of areas on the screen S (indicating the areas R _{1 to} R ₄ ) can be uniform, but the brightness of the entire screen S (in other words, the brightness between the areas) is uniform. Don't be. Therefore, these individual differences are corrected at the time of shipment, and calibration is performed so that the brightness of the projected image on the entire screen S is uniform.

  However, it is not possible to correct the variation of the light source over time between the projector units only by performing calibration at the time of shipment. For this reason, for example, when the multi-vision system 10 is continuously used for a long time, luminance unevenness occurs in the area unit on the screen S. In the multivision system 10 of the present embodiment, the occurrence of the luminance unevenness is prevented by the configuration and operation described below.

As shown in FIG. 2, the projector unit P ₁ includes a first signal processing unit 242, a second signal processing unit 244, a first data storage unit 252, a second data storage unit 254, and a third signal processing unit 242. A data storage unit 256 is included. As shown in FIG. 3, the liquid crystal projector unit 200 includes a first sensor 224 and a second sensor 228. The first sensor 224 and the second sensor 228 are connected to the first signal processing unit 242 and the second signal processing unit 244, respectively.

  The first sensor 224 is a light receiving sensor for measuring the effective luminous intensity of the light source 202. The first sensor 224 is at a position where the light intensity can be measured, and is installed outside the optical path of the liquid crystal projector unit 200. Specifically, it is in the vicinity of the light source 202 and is installed between the light source 202 (more precisely, parabolic mirror 202b) and the fan 226. The lamp 202a emits light having a very high intensity. For this reason, some visible light leaks outward from the parabolic mirror 202b. The first sensor 224 receives the leakage light to realize the light intensity measurement.

  In this specification, the “optical path” is a path of light rays radiated from the lamp 202a and reaching the screen S, and represents a path along which a component contributing to the formation of a projected image on the screen S travels. .

  The closer the position of the first sensor 224 is to the light source 202, the more light can be received. However, the lamp 202a also emits heat rays together with the visible light. For this reason, the closer the position of the first sensor 224 is to the light source 202, the higher the temperature of the first sensor 224 due to the heat rays as a trade-off. In order to improve this, in the liquid crystal projector unit 200 of the present embodiment, the first sensor 224 is installed at a position where the cooling air of the fan 226 hits. By cooling the first sensor 224 with cooling air, it is possible to reduce the performance degradation due to heat. Accordingly, the first sensor 224 can be disposed closer to the light source 202. When arranged as close as possible to the light source 202, the first sensor 224 can receive more light. As a result, the first sensor 224 can output a signal having a high S / N ratio.

  As described above, the first sensor 224 receives the light leaking out of the optical path. In other words, a component that does not contribute to the formation of the projected image on the screen S is received. For this reason, the first sensor 224 is not projected onto the screen S.

  The second sensor 228 is a light receiving sensor for measuring the intensity of light emitted from the projection optical system 222. The second sensor 228 is a position where the intensity can be measured, and is installed outside the optical path in the same manner as the first sensor 224. Specifically, it is installed in front of and around the projection optical system 222. Similarly to the first sensor 224, the second sensor 228 also receives components (for example, scattered light and leakage light) that do not contribute to the image formation of the projected image on the screen S.

  The first signal processing unit 242 and the second signal processing unit 244 process (for example, amplify, A / D conversion, etc.) the signals output from the first sensor 224 and the second sensor 228, respectively, and perform system control. Output to unit 100.

  Next, the first data storage unit 252, the second data storage unit 254, and the third data storage unit 256 will be described.

The first data storage unit 252 includes an output value of the first signal processing unit 242 and a luminance value (cd / m ² ) (or illuminance (lx) and brightness (ANSI Lumen) on the screen S corresponding to the output value. Etc.) are stored. This table is created in advance in the projector unit P ₁ during manufacturing. The “output value of the first signal processing unit 242” is an output value of a signal output by processing the signal acquired from the first sensor 224, and binary data output to the system control unit 100. (Or ASCII data of a digital multimeter).

  The light source 202 can be selectively turned on in two modes of a normal mode and an energy saving mode, for example, by a user operation. The energy saving mode is a mode in which the light intensity of the light source 202 is suppressed as compared with the normal mode. For example, the energy saving mode is a mode in which lighting is performed in a state where power is saved by 20% as compared with the normal mode. When creating the table, for example, the luminous intensity of the light source 202 is changed (that is, the mode is changed), and the output value of the first signal processing unit 242 and the luminance value on the screen S in each mode are measured. The luminance value on the screen S is measured using, for example, an illuminometer or luminance meter. At this time, in order to improve measurement accuracy, it is desirable to project a white uniform image on the screen S.

FIG. 4A is a graph showing the relationship between the output value of the first signal processing unit 242 and the luminance value on the screen S. The sampling number of the measurement data may be at least one point in each mode (that is, at least two points). Each measurement data is linearly interpolated to create a relational expression between the output value of the first signal processing unit 242 and the luminance value on the screen S. This relational expression is, for example,
y = αx + β
It is represented by Note that “x” indicates an output value of the first signal processing unit 242 and “y” indicates a luminance value on the screen S. α and β are coefficients.

  After creating the above relational expression, for example, a representative value of 1024 points is sampled using the expression. The sampled representative values are stored in the first data storage unit 252 as a table. By sampling a plurality of representative values into a table, the burden of processing to be described later executed by the system control unit 100 is reduced. Further, when it is desired to secure the storage area of the first data storage unit 252, the relational expression may be stored as an alternative to the table.

  In order to ensure the linearity between the output value of the first signal processing unit 242 and the luminance value on the screen S, the gain of the first signal processing unit 242 is set so that the output value in the normal mode is not saturated. It is desirable.

  The third data storage unit 256 stores a table (or relational expression) that associates the output value of the second signal processing unit 244 with the corresponding luminance value on the screen S. The table of the third data storage unit 256 is created in the same manner as that of the first data storage unit 252. The “output value of the second signal processing unit 244” is an output value of a signal output by processing the signal acquired from the second sensor 228, and is binary data output to the system control unit 100. (Or ASCII data of a digital multimeter).

The second data storage unit 254 stores a table (or relational expression) that associates the brightness adjustment parameter value with the corresponding brightness value on the screen S. This table is also created projector unit P ₁ previously at the time of manufacture. The “brightness adjustment parameter value” is, for example, a contrast (or brightness) value. The contrast (or brightness) value can be changed, for example, by controlling the transmittance of the three transmissive liquid crystal panels with the projector control unit 230.

  When creating the table, for example, the transmittance of three transmissive liquid crystal panels is varied, and the luminance value on the screen S at each transmittance (that is, each contrast value) is measured. At the time of measurement, the transmittance of each transmissive liquid crystal panel is set to be the same.

FIG. 4B is a graph showing the relationship between the contrast value and the luminance value on the screen S. There should be at least two sampling points of measurement data. A relational expression between the contrast value and the luminance value on the screen S is created using each sampling value. Specifically, linear interpolation is performed between the sampling value having the lowest contrast and the zero point (that is, the point having the contrast “0” and the luminance value “0”). Next, linear interpolation is performed on adjacent sampling values. Furthermore, a relational expression is created by performing an interpolation process so that the luminance value for a contrast value equal to or higher than the sampling value having the highest contrast is constant. The reason why the relational expression having linearity is not created as in the example of FIG. 4A is that there is a gamma characteristic between the contrast value and the luminance value on the screen S. In order to create a relational expression that faithfully reproduces the characteristics (that is, y = x ^γ , “x” represents a contrast value, and “y” represents a luminance value on the screen S), the number of measurement data samples is The more it is, the better.

  After creating the above relational expression, for example, a representative value of 1024 points is sampled using the expression. The sampled representative values are stored in the second data storage unit 254 as a table. Further, when it is desired to secure the storage area of the second data storage unit 254, the relational expression may be stored as an alternative to the table.

  Note that the table stored in the second data storage unit 254 is created corresponding to one of the modes. However, this table may be created in two systems corresponding to each mode.

  Next, a process for realizing the occurrence of uneven luminance in the area unit on the screen S will be described. FIG. 5 is a flowchart showing the processing. This process is executed by the system control unit 100. This process starts when the power supply of the multi-vision system 10 is turned on and ends when it is turned off.

  When the power supply of the multi-vision system 10 is turned on, the system control unit 100 performs time-measurement processing by, for example, time measuring means (not shown) and waits for a predetermined time (for example, 5 minutes) until the light emission amount of the lamp 202a is stabilized (step 1, In the following specification and drawings, steps are abbreviated as “S”). At this time, the mode of the light source 202 is set according to the table stored in the second data storage unit 254. That is, when the above table associates the contrast value in the normal mode with the luminance value on the screen S, the mode of the light source 202 is set to the normal mode. When the table associates the contrast value in the energy saving mode with the luminance value on the screen S, the mode of the light source 202 is set to the energy saving mode. When a table corresponding to both modes is stored in the second data storage unit 254, the mode of the light source 202 can be arbitrarily set by a user operation or the like, for example.

  When the light emission amount of the lamp 202a is stabilized after a predetermined time has elapsed (S1: YES), the system control unit 100 acquires the output value of the first signal processing unit 242 of each projector unit (S2). Next, the first data storage unit 252 of each projector unit is read with reference to each acquired output value, and the corresponding luminance value is acquired (S3). That is, the system control unit 100 acquires the luminance value of each area on the screen S based on the light leaking from the parabolic mirror 202b.

  The system control unit 100 refers to the acquired brightness value of each area and identifies the projector unit that projects the image with the lowest brightness. Then, the specified projector unit is set as a reference projector unit (S4). Note that the projector unit that projects an image with the lowest luminance is used as a reference because the luminance on the screen is as bright as possible in consideration of the life of the light source.

  Following the setting of the reference projector unit, the system control unit 100 reads the second data storage unit 254 of each projector unit other than the reference projector unit, and acquires a contrast value corresponding to the luminance of the reference projector unit (S5). Further, the projector control unit 230 of each projector unit is instructed to set the transmittance corresponding to the read contrast value (S6). Each projector control unit 230 sets the transmittance of each transmissive liquid crystal panel in response to this command. As a result, an image is projected with substantially the same brightness in each area on the screen S.

  The system control unit 100 sets each contrast value and returns to the process of S2 after a predetermined timing. After returning, the above-described series of processing is repeatedly executed. Therefore, even if there is a variation in the temporal change of the light source 202 between the projector units, it is corrected in real time at every predetermined timing. For this reason, for example, even when the multivision system 10 is continuously used for a long time, the luminance unevenness in the region unit on the screen S does not substantially occur.

  In the present embodiment, the first sensor 224 receives the light leaking from the parabolic mirror 202b, thereby realizing luminance measurement. That is, the first sensor 224 is installed so as to receive a component that does not contribute to the formation of the projected image on the screen S. For this reason, the image is not projected on the screen S. Therefore, even if the luminance correction is performed in real time, there is no problem with the image that is played on the screen S.

  Further, by performing luminance measurement using light leaked from the parabolic mirror 202b, highly accurate luminance measurement is realized regardless of the content (color, brightness, etc.) of the projected image.

  Here, as described above, there are individual differences in the light sources. For this reason, for example, when the light source 202 is replaced due to a life or failure, even if the processing of the flowchart of FIG. 5 is executed using the table stored in the first data storage unit 252, the area unit is displayed on the screen S. Brightness unevenness may occur. This is because the table is created in accordance with the characteristics of the light source 202 before replacement.

  Therefore, in the present embodiment, the processing shown in the flowchart of FIG. 6 is executed to prevent occurrence of uneven brightness even after the light source 202 is replaced. This process is executed by the system control unit 100. When the system control unit 100 detects the replacement of the light source 202 by, for example, a user operation, the process of this flowchart is started.

  When the system control unit 100 detects the replacement of the light source 202, the system control unit 100 determines whether or not a predetermined time has passed since the multivision system 10 was turned on (S11). If the system control unit 100 determines that a predetermined time has elapsed since the power was turned on (S11: YES), the system control unit 100 determines that the light emission amount of the lamp 202a is stable and proceeds to the processing of S12.

  In the process of S12, the system control unit 100 acquires the output value of the second signal processing unit 244 of the target projector unit (that is, the light source 202 has been replaced). Next, the third data storage unit 256 of the projector unit is read with reference to the acquired output value, and the corresponding luminance value is acquired (S13). That is, the system control unit 100 acquires the luminance value of a certain area on the screen S (that is, the area projected by the target projector unit) based on the light emitted from the projection optical system 222.

  On the other hand, the system control unit 100 acquires the output value of the first signal processing unit 242 of the target projector unit (S14). Next, referring to the acquired output value, the first data storage unit 252 of the projector unit is read, and the corresponding luminance value is acquired (S15). That is, the system control unit 100 acquires the luminance value of the region on the screen S based on the light leaking from the parabolic mirror 202b of the light source 202 after replacement.

  Next, the system control unit 100 compares the brightness values acquired in the processes of S13 and S15 and determines whether or not the absolute value of the difference is within a predetermined value n (S16). When it is determined that the absolute value is within the predetermined value n (S16: YES), it is determined that there is substantially no individual difference between the light source 202 before and after replacement, and the processing of this flowchart is terminated. On the other hand, when it is determined that the absolute value is greater than the predetermined value n (S16: NO), it is determined that there is an individual difference between the light source 202 before and after replacement, and the process proceeds to S17.

  In the processing of S17, the system control unit 100 acquires the output values of the first signal processing unit 242 and the second signal processing unit 244 at least one point in each mode as described above, and performs the first signal processing from the data. The output value of the unit 242 and the screen brightness data at that time are acquired and linearly interpolated to create a relational expression that matches the characteristics of the light source 202 after replacement. Next, a table is created using this relational expression, the first data storage unit 252 is rewritten (S18), and the processing of this flowchart is terminated. Thereby, the table stored in the first data storage unit 252 is adapted to the characteristics of the light source 202 after replacement. By rewriting the table in accordance with the characteristics of the light source 202 in this way, the occurrence of uneven brightness in the region unit on the screen S is prevented even after the light source 202 is replaced.

  Similarly to the first sensor 224, the second sensor 228 is installed so as to receive a component that does not contribute to the image formation of the projected image on the screen S. For this reason, the image is not projected on the screen S. Therefore, even if the luminance correction is performed in real time, there is no problem with the image that is played on the screen S. When the second sensor 228 performs brightness adjustment in real time, it is necessary to estimate the brightness value of each region based on the integral value of the brightness component of the image signal for a certain period of time and the sensor output value, and to operate the adjustment function. There is.

  The above is the embodiment of the present invention. The present invention is not limited to these embodiments and can be modified in various ranges. For example, the arrangement of each sensor is not limited to that of this embodiment. For example, the first sensor 224 may be installed at a position where the fan 226 is interposed between the first sensor 224 and the light source 202. In this case, the first sensor 224 receives the leaked light through the blades rotated by the fan 226 and outputs a signal.

  Further, the system control unit 100 exists independently in this embodiment, but in another embodiment, the system control unit 100 may be incorporated as a component in any projector unit.

  Each data storage unit is incorporated in each projector unit in the present embodiment, but may be incorporated in the system control unit 100 in another embodiment.

  The second sensor 228, the second signal processing unit 244, and the third data storage unit 256 are components that are required after the light source 202 is replaced. In other words, these components are not necessary when the replacement of the light source 202 is not assumed.

  In the present embodiment, the mode of the light source 202 is set in accordance with the table stored in the second data storage unit 254 when executing the processing of FIG. 5, but in another embodiment, this mode is set. It is not necessary to set according to the above table. That is, when the above table associates the contrast value in the normal mode with the luminance value on the screen S, the mode of the light source 202 may be set to the energy saving mode. In this case, the correction process for multiplying the luminance value in the table by 3/4 is performed, and then the process of FIG. 5 is executed. Further, when the above table associates the contrast value in the energy saving mode with the luminance value on the screen S, the mode of the light source 202 may be set to the normal mode. In this case, the correction process for multiplying the luminance value in the table by 4/3 is performed, and then the process of FIG. 5 is executed.

  In this embodiment, a liquid crystal projector is employed in the multi-vision system. In another embodiment, a micro display device such as DMD (Digital MicroMirror Device: registered trademark of Texas Instruments) or LCOS (reflection type liquid crystal element) is used. The rear and front projection projectors used can also be employed.

It is the figure which showed schematically the structure of the multivision system of embodiment of this invention. It is the block diagram which showed the structure of the projector unit of embodiment of this invention. It is the figure which showed schematically the structure of the liquid-crystal projector part of embodiment of this invention. FIG. 4A is a graph showing the relationship between the output value of the first signal processing unit and the luminance value on the screen. FIG. 4B is a graph showing the relationship between the contrast value and the luminance value on the screen. It is the flowchart which showed the process for implement | achieving generation | occurrence | production prevention of the brightness nonuniformity in the area unit on a screen. It is the flowchart which showed the process for preventing generation | occurrence | production of brightness nonuniformity after light source replacement | exchange.

Explanation of symbols

10 Multivision System 100 System Control Unit 200 Liquid Crystal Projector Unit 224 First Sensor 228 Second Sensor 242 First Signal Processing Unit 244 Second Signal Processing Unit 252 First Data Storage Unit 254 Second Data Storage Unit 256 third data storage unit _P 1 to P ₄ projector unit _R 1 to R ₄ area S screen

Claims (14)

In projector units that make up a multi-vision system,
A light source;
A light source sensor for measuring the intensity of light emitted from the light source;
Luminance data acquisition means for acquiring luminance data corresponding to the measured intensity;
Parameter adjusting means for adjusting parameters related to the brightness of the projected image based on the acquired brightness data, and
A projector unit, wherein the light source sensor is installed outside an optical path.   The projector unit according to claim 1, wherein the light source sensor is installed so as to receive leakage light from the light source. The light source has a lamp that emits light, and a reflecting mirror formed to cover a part of the lamp,
The projector unit according to claim 1, wherein the light source sensor is installed so as to receive light leaking from the reflecting mirror. A cooling means for cooling the light source;
The projector unit according to any one of claims 1 to 3, wherein the light source sensor is installed at a position cooled by the cooling means. A projection optical system that emits projection light;
The projection light sensor for measuring the intensity of the projection light, further comprising: a projection light sensor installed outside the optical path and facing the projection optical system. The projector unit according to claim 1.   6. The projector unit according to claim 5, wherein the projection light sensor is installed so as to receive leakage light from the projection optical system. When the luminance data acquisition means holds a table associating the luminance data with the intensity measured by the light source sensor,
7. The projector unit according to claim 5, further comprising table updating means for updating the table based on the intensity measured by the light source sensor and the projection light sensor. .   8. The projector unit according to claim 1, wherein the parameter relating to the brightness of the projected image is contrast or brightness. A liquid crystal panel for forming a projected image;
The projector unit according to claim 1, wherein the parameter adjusting unit adjusts the transmittance of the liquid crystal panel. In projector units that make up a multi-vision system,
An intensity measurement sensor that measures the intensity of a component that does not contribute to the formation of a projected image;
Luminance data acquisition means for acquiring luminance data corresponding to the measured intensity;
Parameter adjusting means for adjusting parameters related to the brightness of the projected image based on the acquired brightness data, and
A projector unit, wherein the intensity measurement sensor is installed outside the optical path. A multi-vision system comprising a plurality of projector units according to any one of claims 1 to 10,
Brightness data comparison means for comparing the brightness data acquired by the brightness data acquisition means of each projector unit;
Reference setting means for setting a projector unit satisfying a predetermined condition as a reference projector unit based on the comparison result;
A multi-vision system comprising: parameter adjustment control means for controlling each of the parameter adjustment means so that an image is projected at a brightness equivalent to that of the reference projector unit in all projector units.   12. The multi-vision system according to claim 11, wherein the reference setting unit sets a projector unit that projects an image with the lowest luminance as satisfying the predetermined condition. A light source, a light source sensor installed outside the optical path for measuring the intensity of light emitted from the light source, and a first memory storing brightness data of a projected image on the screen corresponding to the intensity Unit, a parameter adjusting unit capable of adjusting a parameter value related to the brightness of the projected image, and a second storage unit storing brightness data of the projected image on the screen corresponding to the parameter value A multi-vision system with multiple units,
First reading means for reading the corresponding luminance data from each of the first storage units with reference to the intensity measured by the light source sensor of each projector unit;
Luminance data comparison means for comparing each read luminance data;
Based on the comparison result, reference setting means for setting a projector unit that projects an image with the lowest luminance as a reference projector unit;
Parameter adjustment for controlling each of the parameter adjustment means with reference to the second storage unit provided other than the reference projector unit so that an image is projected with the same luminance as that of the reference projector unit in all projector units. A multi-vision system characterized by comprising control means. Each of the projector units is a projection optical system that emits projection light, and a projection light sensor for measuring the intensity of the projection light, and is installed outside the optical path and facing the projection optical system And further having a sensor for
The multi-unit according to claim 13, further comprising a first storage update unit that updates the first storage based on the intensity measured by the light source sensor and the projection light sensor. Vision system.

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