JP2021139947A - Image display device, display control method, and cradle - Google Patents

Abstract

To provide an image display device, a display control method, and a cradle, by which the uniformity can be corrected with a simple structure.SOLUTION: An image display device according to an embodiment includes a tablet terminal 10 including a display 11, a cradle 20 holding the tablet terminal 10, a light sensor 30 provided to the cradle 20 and capable of receiving the display light from the display 11, a movable mechanism changing the light-receiving position of the light sensor 30 with respect to the display, a luminance measurement unit 103 that measures the detected luminance of the light sensor 30 in association with the light-receiving position, and a characteristic correction unit 106 correcting the uniformity characteristic of the display on the basis of the measurement result of the detected luminance.SELECTED DRAWING: Figure 3

Description

The present invention relates to an image display device, a display control method, and a cradle.

Some image display devices such as liquid crystal displays have a function of performing more precise display image quality adjustment. For example, there are a medical monitor that interprets medical images, a DTP (DeskTop Publishing) monitor that designs publications, and the like. The liquid crystal display of Non-Patent Document 1 is provided with a sensor function for measuring the display characteristics of the display screen on the bezel portion.

https://www3.jvckenwood.com/pro/healthcare_sys/cl-s300/ [Search on January 6, 2nd year of Reiwa]

By the way, there is a demand for adjusting the display image quality also in a tablet terminal. In particular, medical monitors are required to have higher display characteristics. For example, medical standards define test methods for uniformity and tolerance differences. Note that uniformity is a characteristic that indicates partial brightness variation of the display screen.

When correcting uniformity, it is necessary to measure the brightness distribution of the display. Therefore, the user measures the brightness distribution of the display using an optical sensor. For example, in order to measure the brightness distribution of a display, the display displays a test pattern for measurement. Then, the user moves the position of the optical sensor according to the test pattern, so that the measurement at a plurality of measurement points is performed. As described above, in order to correct the uniformity, there is a problem that the user must perform complicated measurement.

The present disclosure has been made in view of the above points, and an object of the present disclosure is to provide an image display device, a display control method, and a cradle capable of correcting uniformity with a simple configuration.

The image display device according to the present embodiment includes a tablet terminal having a display, a cradle holding the tablet terminal, an optical sensor provided on the cradle and capable of receiving display light from the display, and the display with respect to the display. A movable mechanism that changes the light receiving position of the optical sensor, a brightness measuring unit that measures the detected brightness of the optical sensor in association with the light receiving position, and a uniformity characteristic of the display based on the measurement result of the detected brightness. It is equipped with a characteristic correction unit for correction.

The display control method of the image display device according to the present embodiment includes a tablet terminal having a display, a cradle for holding the tablet terminal, and an optical sensor provided on the cradle and capable of detecting display light from the display. A display control method for an image display device provided, the step of changing the light receiving position of the optical sensor with respect to the display, the step of measuring the detection brightness of the optical sensor in association with the light receiving position, and the detection. It includes a step of correcting the uniformity characteristics of the display based on the measurement result of the brightness.

The cradle according to the present embodiment includes a holding unit that holds the tablet terminal, an optical sensor that detects display light from the display of the tablet terminal, a movable mechanism that changes the light receiving position of the optical sensor with respect to the display, and the above. It includes a luminance measuring unit that measures the detected luminance of the optical sensor in association with the light receiving position, and a characteristic correcting unit that corrects the uniformity characteristics of the display based on the measurement result of the detected luminance.

According to the present disclosure, it is an object of the present invention to provide an image display device, a display control method, and a cradle capable of correcting uniformity with a simple configuration.

It is a figure which shows the whole structure of the image display device which concerns on this Embodiment 1. It is a schematic diagram explaining the light receiving position of an optical sensor on a display. It is a block diagram which shows the control system of an image display device. It is a figure which shows the difference of the display image depending on the presence / absence of uniformity correction. It is a flowchart which shows the display control method of an image display device. It is a schematic diagram which shows the measurement pattern in the image display apparatus which concerns on Embodiment 2. It is a schematic diagram which shows the movement locus of an optical sensor in the image display device which concerns on Embodiment 3.

Hereinafter, specific embodiments to which the present invention is applied will be described in detail with reference to the drawings. However, the present disclosure is not limited to the following embodiments. In addition, the following description and drawings have been simplified as appropriate to clarify the description.

Embodiment 1.
The image display device 100 according to the present embodiment will be described with reference to FIG. FIG. 1 is a diagram showing an image display device 100. FIG. 1 is a perspective view of the tablet terminal 10 as viewed from the front side. The image display device 100 includes a tablet terminal 10 and a cradle 20. The tablet terminal 10 has a display 11. The approximate shape of the tablet terminal 10 is rectangular.

The display 11 has a liquid crystal display panel, an organic EL (electro-luminescence) display panel, and the like, and displays a desired image. That is, the image is displayed by the display light from the display 11. Further, the display 11 is provided with a touch panel for performing a touch operation. The display 11 has a rectangular shape, and the periphery thereof is a bezel (housing). Further, a camera or the like may be provided on the bezel portion of the tablet terminal 10.

The tablet terminal 10 has communication functions such as Wi-Fi (registered trademark) and Bluetooth (registered trademark). Further, the tablet terminal 10 is provided with a processor, a memory, a microphone, a speaker, a camera, a vibrator, a button and the like. The tablet terminal 10 stores an OS (Operating System) program such as an android (registered trademark) and an application program (application) running on the OS in a memory. The tablet terminal 10 may include a smartphone having a call function such as a telephone. Of course, the configuration of the tablet terminal 10 is not particularly limited. The tablet terminal 10 may have a display 11 and may not have all of the above configurations.

The cradle 20 holds the tablet terminal 10 in a detachable manner. The cradle 20 has a holding portion 21 for holding the tablet terminal 10. When the tablet terminal 10 is placed on the cradle 20, the tablet terminal 10 is held in a standing position. The tablet terminal 10 is held with the display 11 facing diagonally upward.

The cradle 20 includes a charging terminal (not shown) and the like, and charges the tablet terminal 10. That is, when the user places the tablet terminal 10 on the cradle 20, the charging terminal of the cradle 20 is inserted into the charging port of the tablet terminal, and charging is started. Of course, the tablet terminal 10 may be charged by non-contact charging. Further, the cradle 20 may be provided with a charging port, connectors for various interfaces, and input / output terminals (all not shown).

The cradle 20 is provided with an optical sensor 30 that makes measurements for adjusting the display image quality. The optical sensor 30 detects the display light from the display 11. Uniformity correction is applied to the display 11 based on the detection result of the optical sensor 30. The optical sensor 30 includes a photodiode, a CCD (Charge Coupled Devices) camera, a CMOS (Complementary Metal Oxide Semiconductor) sensor, and the like. The optical sensor 30 outputs a detection signal according to the amount of detected light. The optical sensor 30 is arranged so as to face the display 11. The optical sensor 30 is attached to the cradle 20 so as to face the display screen of the display 11.

The cradle 20 has an arm 40. The arm 40 supports the optical sensor 30. The optical sensor 30 is attached to the arm 40. An arm 40 is provided between the cradle 20 and the optical sensor 30. An optical sensor 30 is provided at one end (tip) of the arm 40, and the other end (base end) of the arm 40 is attached to the cradle 20. In the arm 40, there is a rotation shaft 41 at the base end on the cradle 20 side. The optical sensor 30 is attached to the cradle 20 via the arm 40.

The arm 40 is a movable mechanism that moves the light receiving position of the optical sensor 30 with respect to the display 11. For example, the arm 40 is provided with an actuator such as a motor. Then, the optical sensor 30 moves by driving the actuator.

The arm 40 extends parallel to the surface of the display 11. The arm 40 is a rotating arm that rotates in the direction of the arrow R with the rotating shaft 41 as the center of rotation. That is, the optical sensor 30 moves in an arc shape centered on the rotation axis 41. The optical sensor 30 rotates and moves on the display 11 of the tablet terminal 10.

Further, the arm 40 is a telescopic arm having a telescopic portion 42. As the telescopic portion 42 slides in the direction of the arm, the arm 40 expands and contracts in the direction of the arrow S. As a result, the length of the arm 40 changes, so that the distance between the optical sensor 30 and the rotating shaft 41 changes.

In this way, the operation of the arm 40 causes the optical sensor 30 to move along the surface of the display 11. Specifically, the arm 40 is provided with an actuator for changing the rotation angle and the amount of expansion and contraction, respectively. In the above description, the telescopic and rotatable arm 40 is used as the movable mechanism, but the movable mechanism is not limited to the configuration shown in FIG.

The arm 40 allows the optical sensor 30 to be moved from the outside to the front of the display 11. Further, the arm 40 can change the light receiving position of the optical sensor 30. By controlling the rotation angle and the amount of expansion and contraction of the arm 40, the optical sensor 30 can be moved to an arbitrary position on the display 11. By changing the light receiving position of the optical sensor 30, the brightness distribution (uniformity characteristic) of the display 11 can be measured.

An example of the position of the light receiving position with respect to the display 11 will be described with reference to FIG. FIG. 2 is a schematic diagram for explaining a light receiving position of the optical sensor 30 with respect to the display 11. In FIG. 2, the image display device 100 is simplified. For example, in FIG. 2, the cradle 20, the telescopic portion 42, and the like are omitted.

In FIG. 2, the arm 40 changes the optical sensor 30 to the light receiving positions A to E. That is, the optical sensor 30 moves in the order of the light receiving positions A to E by changing the rotation angle and the expansion / contraction amount of the arm 40. Then, the optical sensor 30 detects the display light at the light receiving positions A to E. Here, the light receiving position A corresponds to the center of the display 11. The light receiving positions B to E correspond to the vicinity of the square of the display 11. Of course, the location and number of light receiving positions of the optical sensor 30 are not limited to the example of FIG.

For example, the optical sensor 30 detects the display light from the display 11 while the optical sensor 30 faces the display 11 at the light receiving position A. This makes it possible to measure the brightness at the center of the display 11. Similarly, at the light receiving positions B to E, the optical sensor 30 detects the display light from the display 11. This makes it possible to measure the brightness distribution of the display 11. The uniformity correction of the display 11 is performed based on the detection result of the optical sensor 30.

FIG. 3 is a control block diagram showing a control system for performing uniformity correction. The image display device 100 includes a correction control unit 101, a measurement pattern generation unit 102, a display 11, an optical sensor 30, a brightness measurement unit 103, an arm control unit 105, a characteristic correction unit 106, and a size identification unit 108. And have. The correction control unit 101 controls each control block in order to perform uniformity correction.

A command from the correction control unit 101 is input to the arm control unit 105. The arm control unit 105 controls the arm 40 based on a command from the correction control unit 101. The arm control unit 105 outputs a control signal for controlling an actuator such as a motor. By driving the actuator of the arm 40, the arm 40 rotates or expands and contracts. As a result, as shown in FIG. 2, the optical sensor 30 moves in the order of the light receiving positions A to E.

The measurement pattern generation unit 102 generates a measurement pattern based on a command from the correction control unit 101. The display 11 displays the measurement pattern. While the measurement pattern is displayed, the optical sensor 30 detects the display light from the display 11. The brightness measuring unit 103 measures the detected brightness of the optical sensor 30 in association with the light receiving position. When the optical sensor 30 detects the display light at a plurality of light receiving positions, the luminance measuring unit 103 can measure the luminance distribution (uniformity) of the display 11. The characteristic correction unit 106 corrects the uniformity characteristic according to the measurement result of the detected luminance.

The measurement pattern is, for example, a gray pattern in which at least a part of the display screen is uniform. That is, the measurement pattern is an image in which the gradation level is uniform at a position near the measurement point (light receiving position) by the optical sensor 30.

For example, as shown in FIG. 2, the region near the measurement point is defined as the measurement regions 110A to 110E. In the measurement areas 110A to 110E, the display 11 has a uniform gradation level. A uniform gray pattern is displayed in each of the measurement areas 110A to 110E. When the center of the display 11 is the light receiving position A, the periphery of the center of the display 11 is the measurement area 110A. The measurement area 110A is a region including the light receiving position A. For example, the measurement area 110A overlaps with the optical sensor 30 at the light receiving position A. Further, the measurement region 110A is a region larger than the optical sensor 30.

When the upper left corner of the display 11 is the light receiving position B, the vicinity of the upper left corner of the display 11 is the measurement area 110B. When the upper right corner of the display 11 is the light receiving position C, the periphery of the upper right corner of the display 11 is the measurement area 110C. When the lower right corner of the display 11 is the light receiving position D, the periphery of the lower right corner of the display 11 is the measurement area 110D. When the lower left corner of the display 11 is the light receiving position E, the vicinity of the lower left corner of the display 11 is the measurement area 110E.

In this way, the positions of the measurement areas 110A to 110E change according to the light receiving positions A to E of the optical sensor 30. That is, the measurement pattern is switched every time the light receiving position is changed. The measurement pattern generation unit 102 generates a measurement pattern that changes according to the light receiving position. The position of the measurement area on the display 11 is associated with the rotation angle and the expansion / contraction amount of the arm 40.

The centers of the measurement areas 110A to 110E coincide with the light receiving positions A to E. The measurement pattern generation unit 102 generates a measurement pattern so that the measurement region matches the light receiving position. Therefore, the optical sensor 30 can detect the display light from the measurement area. That is, the optical sensor 30 detects the display light from the measurement area while the uniform gray pattern is displayed in the measurement area.

In areas other than the measurement areas 110A to 110E, for example, the display 11 may be displayed in black. Of course, the area other than the measurement area may be other than the black display. In FIG. 2, the measurement areas 110A to 110E are all rectangular areas having the same size. Of course, the measurement areas 110A to 110E may have shapes other than rectangles (for example, polygons other than rectangles, circles, ellipses, etc.), and may have different sizes and shapes.

Further, the measurement pattern generation unit 102 generates a plurality of gray patterns having different gradation levels by switching them at regular time intervals. As an example, the gradation level gradually changes from black to white with time. For example, in the measurement area 110A, the gradation level of the gray pattern is switched in the order of G1, G2, ... Gn (n is an integer of 2 or more). The optical sensor 30 detects the display light at each of the gradation levels G1 to Gn. As a result, the measurement at the light receiving position A is completed.

Next, the arm 40 moves the optical sensor 30 to the light receiving position B in order to perform the measurement at the light receiving position B. Then, in the measurement area 110B, the gradation level of the gray pattern is switched in the order of G1, G2, ... Gn (n is an integer of 2 or more). The optical sensor 30 detects the display light at each of the gradation levels G1 to Gn. As a result, the measurement at the light receiving position B is completed. Also at the light receiving positions C to E, the measurement pattern generation unit 102 switches the measurement pattern so as to perform the measurement at the plurality of gradation levels G1 to Gn in the same manner.

In this way, the correction control unit 101 controls the arm control unit 105 and the measurement pattern generation unit 102. Therefore, the measurement pattern generation unit 102 can generate a measurement pattern according to the light receiving position of the optical sensor 30. That is, the correction control unit 101 is preset with the light receiving position on the display 11. Then, the correction control unit 101 outputs a command to the arm control unit 105 and the measurement pattern generation unit 102 according to the preset light receiving position.

The brightness measuring unit 103 measures the detected brightness of the optical sensor 30. The brightness measuring unit 103 measures the detected brightness in association with the light receiving position. That is, the value of the detected luminance is stored for each light receiving position A to E. Further, the luminance measuring unit 103 measures the detected luminance in association with the gradation level. That is, the value of the detected luminance is stored for each gradation level G1 to Gn. By doing so, the luminance measuring unit 103 can measure the luminance distribution of the display 11.

The detection brightness assumed when the display 11 displays the measurement pattern is used as the reference brightness. By comparing the actually detected detected brightness with the reference brightness, the brightness measuring unit 103 calculates the screen brightness information. The brightness measuring unit 103 acquires screen brightness information for each light receiving position. That is, the brightness measuring unit 103 obtains the difference between the detected brightness and the reference brightness for each light receiving position. The brightness measurement unit 103 acquires screen brightness information for each gradation level. The reference luminance is set for each gradation level G1 to Gn. That is, the screen brightness information is calculated for each gradation level G1 to Gn.

The correction control unit 101 outputs a correction signal to the characteristic correction unit 106 based on the screen brightness information. The characteristic correction unit 106 corrects the uniformity characteristics of the display 11 based on the correction signal. The characteristic correction unit 106 may adjust the display luminance distribution by correcting the display gradation level. The characteristic correction unit 106 obtains the display gradation level by adding or subtracting an offset value to or subtracting an offset value from the input gradation level or multiplying it by a gain value (coefficient). When the detected luminance is lower than the reference luminance, the characteristic correction unit 106 outputs a correction signal so that the display luminance level is higher than the input luminance level.

The characteristic correction unit 106 divides the display screen into a plurality of areas and corrects the display gradation level. Here, the plurality of regions are divided according to the plurality of light receiving positions. Alternatively, the display gradation level may be corrected by interpolation for the pixels between the light receiving positions.

Further, the optical sensor 30 measures the brightness for each gradation level. The characteristic correction unit 106 may specify the gamma characteristic of the display 11 based on the brightness of each gradation level. The characteristic correction unit 106 determines whether or not the specified gamma characteristic matches the desired gamma characteristic, and if they do not match, corrects the gamma characteristic of the display 11 to adjust to the desired display characteristic. .. When the correction unit determines that the specified gamma characteristic matches the predetermined gamma characteristic, the correction unit does not adjust the display characteristic of the display 11. The comparison of gamma characteristics may be determined to be in agreement as long as it is within a predetermined range. As a result, a constant display image quality can be maintained.

Of course, not only the display brightness but also the color adjustment may be performed. For example, if the optical sensor 30 is a sensor capable of measuring color characteristics, it can detect RGB luminance information, so that the color of the displayed image can be adjusted. By doing so, the display characteristics of the display 11 for each RGB can be individually and independently corrected. A sensor capable of measuring color characteristics is, for example, a CCD.

In this way, the characteristic correction unit 106 corrects the uniformity of the display 11 according to the brightness distribution measured by the brightness measurement unit 103. It is possible to suppress variations in the brightness distribution of the display 11. For example, the optical sensor 30 receives the display light at the center and the end of the display 11, respectively. Then, by comparing the light receiving results at the center and the edge, it is possible to correct the variation in the luminance distribution. It is possible to suppress uneven brightness (deterioration of uniformity) of the display screen. That is, the characteristic correction unit 106 performs uniformity correction so as to cancel the variation in the luminance distribution.

FIG. 4 is a diagram showing a difference in the displayed image depending on the presence or absence of uniformity correction. In FIG. 4, the display 11 displays a uniform gray pattern. That is, all the pixels of the display 11 have the same gradation level. If there is no correction, the display brightness will be uneven. By performing uniformity correction, a uniform gray pattern can be displayed. This makes it possible to suppress unevenness in display brightness.

Further, a plurality of tablet terminals 10 may correspond to one cradle 20. The plurality of tablet terminals 10 may be a plurality of types of tablet terminals having different screen sizes and display characteristics. A plurality of tablet terminals 10 may share one cradle. For example, two tablet terminals 10 may be alternately placed on one cradle 20. In this case, one cradle 20 can adjust the image quality of the plurality of tablet terminals 10. Adjustments can be made so that the image quality of the plurality of tablet terminals 10 is the same. For example, the display brightness of another tablet terminal 10 can be adjusted so as to be equivalent to the display brightness of one tablet terminal 10.

Tablet terminals 10 of different sizes may be installed on one cradle 20. In this case, the image display device 100 preferably includes a size specifying unit 108. The size specifying unit 108 specifies the size of the display 11 of the tablet terminal 10 installed in the cradle 20. For example, the cradle 20 can hold tablet terminals 10 of different sizes. The size specifying unit 108 specifies the display size of the installed tablet terminal 10.

The light receiving position for obtaining the brightness distribution changes according to the display size. For example, when the center of the display 11 is the light receiving position of the optical sensor 30, the amount of expansion and contraction and the rotation angle of the arm 40 from the rotation shaft 41 to the center of the display 11 change according to the display size. Therefore, the size specifying unit 108 specifies the display size of the tablet terminal 10 held by the cradle 20.

The coordinates of the light receiving position are set in the correction control unit 101 for each display size. That is, the rotation angle and the expansion / contraction amount for moving the optical sensor 30 to the light receiving position are set for each display size. The correction control unit 101 obtains the rotation angle and the expansion / contraction amount of the arm 40 according to the display size specified by the size specifying unit 108. Then, the correction control unit 101 outputs a command to the arm control unit 105 so that the arm 40 has a predetermined rotation angle and expansion / contraction amount.

Further, the correction control unit 101 outputs a command to the measurement pattern generation unit 102 so as to display a uniform gray pattern in the measurement region including the light receiving position. That is, the correction control unit 101 determines the coordinates of the measurement area on the display 11 according to the display size. By doing so, even when tablet terminals 10 of different sizes share one cradle 20, uniformity correction can be appropriately performed.

The method by which the size specifying unit 108 specifies the display size is not particularly limited. For example, the cradle may be provided with magnetic, optical, and mechanical sensors to specify the size and model name of the tablet terminal 10. Alternatively, the cradle 20 and the tablet terminal 10 may transmit and receive signals by wire or wireless communication. Then, the cradle 20 acquires terminal type information such as the model number, model name, and manufacturer name of the tablet terminal 10 from the tablet terminal 10. The correction control unit 101 specifies the display size according to the terminal type information. In this case, the correction control unit 101 may specify the display size by referring to the preset data table. That is, the data table is associated with the terminal type information and the display size. Of course, the size specifying unit 108 may specify the display size by using a method other than the above method.

By doing so, it is possible to more easily correct the uniformity for various tablet terminals 10. Uniformity correction can be automatically performed without the user performing operations such as setting the light receiving position.

The correction control unit 101, the measurement pattern generation unit 102, the brightness measurement unit 103, the arm control unit 105, the characteristic correction unit 106, and the size identification unit 108 may be provided on the tablet terminal 10. Alternatively, the correction control unit 101, the measurement pattern generation unit 102, the brightness measurement unit 103, the arm control unit 105, the characteristic correction unit 106, and the size identification unit 108 may be provided in the cradle 20. Further, a part of the correction control unit 101, the measurement pattern generation unit 102, the brightness measurement unit 103, the arm control unit 105, the characteristic correction unit 106, and the size identification unit 108 is provided in the tablet terminal 10, and the rest is the cradle 20. It may be provided in.

For example, the correction control unit 101, the measurement pattern generation unit 102, and the characteristic correction unit 106 are provided in the tablet terminal 10, and the brightness measurement unit 103, the arm control unit 105, and the size identification unit 108 are provided in the cradle 20. You may. In this case, the brightness measuring unit 103 may transmit the screen brightness information to the tablet terminal 10 by wired communication or wireless communication. That is, if necessary signals and information are transmitted and received between the tablet terminal 10 and the cradle 20, the control system can be distributed and arranged between the tablet terminal 10 and the cradle 20.

Further, some functions of each control block may be provided in the tablet terminal 10, and the rest may be provided in the cradle 20. For example, the tablet terminal 10 and the cradle 20 may work together to realize the function of the correction control unit 101.

The processing in the correction control unit 101, the measurement pattern generation unit 102, the brightness measurement unit 103, the arm control unit 105, the characteristic correction unit 106, and the size identification unit 108 can be realized by a computer program. For example, an application for performing measurement or correction is stored in the tablet terminal 10. The above process is executed when the processor of the tablet terminal 10 executes the application.

FIG. 5 is a flowchart showing a display control method of the image display device 100. First, the user instructs the start of correction of the uniformity characteristic (S11). For example, the user operates a touch panel or the like to touch the correction start button. As a result, the correction control unit 101 receives the instruction to start correction. Alternatively, the correction control unit 101 may automatically start the correction by detecting that the tablet terminal 10 is placed on the cradle 20. Further, the correction control unit 101 may start the correction with the start of charging of the tablet terminal 10 as a trigger.

Next, the size specifying unit 108 specifies the display size of the tablet terminal 10 (S12). As described above, various sensors provided in the cradle 20 may measure the size and model of the tablet terminal 10. Alternatively, the size specifying unit 108 may obtain the terminal type information of the tablet terminal 10 by transmitting and receiving data between the tablet terminal 10 and the cradle 20.

The optical sensor 30 moves to the light receiving position (S13). That is, the arm control unit 105 drives the arm 40 in response to a command from the correction control unit 101. As a result, the optical sensor 30 moves to the light receiving position according to the display size.

The display 11 displays the measurement pattern (S14). That is, in response to a command from the correction control unit 101, the measurement pattern generation unit 102 generates a measurement pattern according to the display size. As a result, a uniform gray pattern is displayed in the measurement area including the light receiving position.

The brightness measuring unit 103 measures the brightness at the light receiving position (S15). That is, the optical sensor 30 detects the display light from the measurement area. As a result, the brightness measuring unit 103 measures the display brightness at the light receiving position.

Then, the correction control unit 101 determines whether or not the measurement of all gradation levels has been completed (S16). When the measurement of all gradation levels is not completed (NO in S16), the display 11 displays the next measurement pattern (S14). That is, the display 11 displays the measurement patterns of different gradation levels. For example, when the measurement at the gradation level G1 is completed, the measurement pattern generation unit 102 generates the next measurement pattern at the gradation level G2. Then, the processes of S14 to S16 are repeated until the measurement of all the gradation levels G1 to Gn is completed.

When the measurement of all gradation levels is completed (YES in S16), it is determined whether or not the measurement at all the light receiving positions is completed (S17). When the measurement at all the light receiving positions is not completed (NO in S17), the optical sensor 30 moves to the next light receiving position (S13). For example, when the measurement at the light receiving position A is completed, the arm 40 moves the optical sensor 30 to the light receiving position B (see FIG. 2). Then, the processes of S13 to S17 are repeated until the measurements at all the light receiving positions A to E are completed.

When the measurement at all the light receiving positions is completed (YES in S17), the characteristic correction unit 106 corrects the uniformity characteristic (S18). That is, the characteristic correction unit 106 calculates an offset value and a gain value for correcting the display gradation level. Then, the characteristic correction unit 106 sets the offset value and the gain value in the tablet terminal 10. By doing so, the uniformity can be corrected appropriately. Therefore, a normal display image can be appropriately displayed.

Since the optical sensor 30 is provided in the cradle 20, the tablet terminal 10 can be made smaller and lighter. The display image quality can be adjusted with a simple configuration. When using the tablet terminal 10, the user removes the tablet terminal 10 from the cradle 20. Since the measurement for adjustment is not performed when the tablet terminal 10 is used, there is no problem even if the cradle 20 is provided with the optical sensor 30.

Further, the optical sensor 30 is arranged so as to be located at the end of the display 11. The optical sensor 30 is preferably configured so as to be in close contact with the display 11. By doing so, it is possible to prevent the ambient light from the interior light or the like from entering the optical sensor 30.

Further, when the measurement is completed, the optical sensor 30 may be moved downward. The optical sensor 30 moves to the outside of the display 11. As a result, the optical sensor 30 is housed in the cradle 20. Even when the tablet terminal 10 is placed on the cradle 20, the user can visually recognize the entire display 11. That is, since the optical sensor 30 moves to the outside of the display screen of the display 11, the display screen of the display 11 is not obstructed.

Embodiment 2.
In the present embodiment, the measurement pattern generated by the measurement pattern generation unit 102 is different from that of the first embodiment. Since the configuration and control other than the measurement pattern are the same as those in the first embodiment, the description thereof will be omitted as appropriate. The image display device and the display control method thereof according to the second embodiment will be described with reference to FIG.

In the present embodiment, a measurement pattern is used so that the entire display screen has a uniform gray pattern. That is, all the pixels of the display 11 have the same gradation level. Then, with the passage of time, the entire display screen gradually changes from black display to white display. Similar to the first embodiment, the optical sensor 30 detects the display light while the display 11 displays the measurement pattern.

In the present embodiment, it is not necessary to move the measurement area according to the light receiving position. Further, the control of changing the position of the measurement area according to the display size becomes unnecessary. Therefore, the uniformity correction can be performed more easily.

Embodiment 3.
The image display device and its control according to the third embodiment will be described with reference to FIG. 7. In the present embodiment, the sequence for moving the optical sensor 30 is different from that in the first and second embodiments. FIG. 7 is a diagram showing a locus 33 in which the optical sensor 30 moves on the display 11. That is, the arm control unit 105 controls the arm 40 so that the optical sensor 30 continuously moves along the locus 33.

The correction control unit 101 presets a sequence pattern of a rotation angle and an expansion / contraction amount for each display size. As a result, the optical sensor 30 moves along the locus 33. By doing so, the moving time of the optical sensor 30 can be shortened, so that the measurement time can be shortened.

The optical sensor 30 detects the display light while moving along the locus 33. The brightness at an arbitrary position on the display screen can be obtained by arithmetic processing such as interpolation. The brightness measuring unit 103 can measure the brightness distribution. Then, the characteristic correction unit 106 performs uniformity correction according to the brightness distribution.

Of course, the movement sequence is not limited to the locus 33 shown in FIG. Any sequence pattern can be appropriately used as the locus 33 according to the size of the display 11, the mounting position of the arm 40, the shape, and the like.

The image display device 100 is suitable for a medical monitor that displays a diagnostic image of a patient. Since the diagnostic image can be stably displayed with an appropriate display image quality, it can contribute to the improvement of diagnostic accuracy. Examples of the diagnostic image include an endoscopic image, an MRI (Magnetic Resonance Imaging) image, a CT (Computed Tomography) image, an X-ray image, and the like. By performing the above display control method, the allowable range of uniformity defined by the medical standard can be easily satisfied. Of course, the image display device 100 is not limited to the medical monitor. For example, the image display device 100 can be applied to a monitor for DTP and a monitor for other purposes.

The above embodiments can be combined as appropriate. Part or all of the above processing may be executed by a computer program. The programs described above can be stored and supplied to a computer using various types of non-transitory computer readable media. Non-transient computer-readable media include various types of tangible storage media. Examples of non-temporary computer-readable media include magnetic recording media (eg, flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (eg, magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / W, semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory)) are included. The program may also be supplied to the computer by various types of temporary computer readable media. Examples of temporary computer-readable media include electrical, optical, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

Although the invention made by the present inventor has been specifically described above based on the embodiment, the present invention is not limited to the above embodiment and can be variously modified without departing from the gist thereof. Needless to say. It is also possible to appropriately combine two or more of the above embodiments.

100 Image display device 10 Tablet terminal 11 Display 20 Cradle 21 Holding unit 30 Optical sensor 40 Arm 101 Correction control unit 102 Measurement pattern generation unit 103 Luminance measurement unit 106 Characteristic correction unit 105 Arm control unit 106 Characteristic correction unit 108 Size identification unit

Claims (6)

A tablet terminal with a display and
The cradle that holds the tablet device and
An optical sensor provided in the cradle and capable of receiving the display light from the display,
A movable mechanism that changes the light receiving position of the optical sensor with respect to the display,
A luminance measuring unit that measures the detected luminance of the optical sensor in association with the light receiving position,
An image display device including a characteristic correction unit that corrects the uniformity characteristics of the display based on the measurement result of the detected luminance. The cradle can hold the tablet terminal of a plurality of sizes.
A size specifying unit that specifies the display size of the tablet terminal held by the cradle, and
The image display device according to claim 1, further comprising a movable mechanism control unit that controls the movable mechanism according to the display size. The movable mechanism includes an arm that supports the optical sensor.
The image display device according to claim 1 or 2, wherein the arm is provided so as to be rotatable and expandable. While the display is displaying the measurement pattern, the optical sensor detects the display light,
The image display device according to any one of claims 1 to 3, wherein in the measurement pattern, the gradation level is uniform in the measurement region including the light receiving position. A tablet terminal with a display and
The cradle that holds the tablet device and
A display control method for an image display device including an optical sensor provided on the cradle and capable of detecting display light from the display.
A step of changing the light receiving position of the optical sensor with respect to the display, and
A step of measuring the detection brightness of the optical sensor in association with the light receiving position,
A display control method of an image display device including a step of correcting the uniformity characteristics of the display based on the measurement result of the detected luminance. A holding part that holds the tablet terminal and
An optical sensor that detects the display light from the display of the tablet terminal,
A movable mechanism that changes the light receiving position of the optical sensor with respect to the display,
A luminance measuring unit that measures the detected luminance of the optical sensor in association with the light receiving position,
A cradle including a characteristic correction unit that corrects the uniformity characteristics of the display based on the measurement result of the detected luminance.

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