WO2007086409A1

WO2007086409A1 - Image display device, image display method, and image processing program

Info

Publication number: WO2007086409A1
Application number: PCT/JP2007/051062
Authority: WO
Inventors: Masayuki Nakazawa
Original assignee: Konica Minolta Medical & Graphic, Inc.
Priority date: 2006-01-26
Filing date: 2007-01-24
Publication date: 2007-08-02

Abstract

Provided are an image display device, an image display method and an image processing program, which can display a monochromatic image in a color tone more suitable for diagnoses and which can select the tendency to change the color tone. This image display device is a color type including a control unit for distributing the monochromatic image data into RGB data so that it displays an image on the basis of the image data distributed by the control unit. This control unit distributes the image data such that a blue tone may be the more intensified for the lower brightness of the monochromatic image data.

Description

Image display apparatus, image display method, and image processing program

Technical field

The present invention relates to an image display device, an image display method, and an image processing program. More specifically, the present invention relates to a color image display device that displays a monochrome image, an image display method, and an image processing program. Background art

[0002] Taken by medical diagnostic equipment, for example, X-ray imaging equipment such as CR (Computed Radiography), MRI (Magnetic Resonance Imaging) diagnostic equipment, various CT (Computed Tomography) equipment, etc. The resulting image is recorded on a light-transmissive image recording film such as an X-ray film or a film photosensitive material. Such an image recording film is set in an observation apparatus called Schukasten, and is observed in a state where it is irradiated with backside light. In this way, the image recorded on the film is observed and a medical diagnosis is performed.

[0003] In medical diagnostic devices and medical measuring devices, CRT (Cathode Ray Tube) displays and LC (Liquid Crystal Displays) are used as image display devices for displaying captured images and measured images. ) Display is connected. In these image display devices, diagnosis based on the displayed image, or confirmation and adjustment of a diagnostic image before film output, image processing, and the like are performed.

[0004] A blue-based monochrome film is usually often used as a film for recording an image taken by a medical diagnostic apparatus or medical measurement apparatus as described above. On the other hand, on the monitor, the image is displayed on the screen based on white. Therefore, it is difficult for a doctor who observes both the film and the screen to switch the sensation between images with different base colors, and for a doctor who is accustomed to images using one base color. However, it is difficult to see an image using the other base color.

[0005] Therefore, when displaying a monochrome image using a color image display device, the image is changed from white base to blue base and displayed, so that the blue base mono display is displayed. A technique for displaying the image with a small difference from the black film is disclosed (for example, patent document)

1 and Patent Document 2). Thus, when displaying an image on a blue base, the higher the luminance, the stronger the blue color.

Patent Document 1: JP 2000-330530 A

Patent Document 2: Japanese Patent Laid-Open No. 2003-295851

Disclosure of the invention

Problems to be solved by the invention

[0006] However, as shown in Patent Document 1 and Patent Document 2, the higher the display brightness is, the stronger the blue color is, the more the image recorded on the blue-based monochrome film is observed on the shukasten. If the present inventors have revealed that the color tone does not match the original color tone, there is a problem!

[0007] In addition, since the tendency of the color tone change depending on the image density varies depending on the type of film, if the tendency of the color tone change with respect to the displayed luminance is uniquely determined, the color tone of the image display device is the same as that of the film. There is a problem that is different from the color tone, or that it is impossible to deal with the color tone of the film preferred by each doctor.

The present invention has been made in view of the above points, and can display a monochrome image in a color tone more suitable for diagnosis, and can select a tendency to change the color tone. It is an object of the present invention to provide an image display device, an image display method, and an image processing program.

Means for solving the problem

[0009] In order to solve such a problem, the invention described in claim 1

A control unit that distributes monochrome image data to RGB image data,

In an image display device for displaying a color image based on the RGB image data distributed by the control unit,

The control unit distributes the monochrome image data to the RGB image data so that the blue color tone becomes stronger as the luminance is lower.

[0010] The invention according to claim 2 is the image display device according to claim 1, wherein the control unit has at least a maximum luminance when displaying the monochrome image data. The monochrome image data is allocated to the RGB image data so that the lower the luminance is, the stronger the color of blue is within the range of LO and the luminance LI that is 1/30 of the maximum luminance LO. .

[0011] The invention according to claim 3 is the image display device according to claim 1 or claim 2, in which the control unit receives the monochrome image data.

R image data = KRX B image data (0 <KR <1)

G image data = KG X B image data (0 <KG <1)

(Here, at least one of KR and KG takes a smaller value as the luminance is lower).

[0012] The invention according to claim 4 is the image display device according to claim 3, wherein at least one of the KR and KG is at least the luminance L0 and the luminance L1. Within the range, the brightness is so low that the value is as small as possible.

[0013] The invention according to claim 5 is the image display device according to claim 3 or claim 4, wherein the KR and KG are at least the luminance L0 and the brightness. It is characterized by being KR and KG within the range of degree L1.

[0014] The invention described in claim 6 is the image display device according to claim 1, wherein the control unit converts the monochrome image data into coordinates (CIE chromaticity diagram). X, y) is characterized in that at least one of the coordinates x and y is distributed so as to decrease at least within the range of the luminance L0 and the luminance L1.

[0015] The invention according to claim 7 is the image display device according to any one of claims 1, 6 and 6,

A color tone input means for inputting a desired color tone;

The control unit distributes the monochrome image data to the RGB image data in accordance with a color tone input by the color tone input unit.

[0016] The invention according to claim 8 is the image display device according to any one of claims 1, 6 and 6,

An observer identification code input means for inputting an observer identification code capable of identifying the observer, and a memory for storing the observer identification code and a desired color tone for each observer in association with each other And comprising

The control unit distributes the monochrome image data to the RGB image data according to a desired color tone of the observer corresponding to the observer identification code input by the observer identification code input unit.

[0017] The invention according to claim 9 is

As an image display method for displaying color images based on RGB image data generated by distributing monochrome image data,

The monochrome image data is distributed to the RGB image data so that the blue color tone becomes stronger as the luminance decreases.

[0018] The invention according to claim 10 is the image display method according to claim 9,

At least within the range of the maximum brightness LO when displaying the monochrome image data and the brightness L1 that is 1/30 of the maximum brightness LO, the monochrome image data is enhanced so that the lower the brightness, the stronger the blue color tone. Is characterized by allocating to RGB image data.

[0019] The invention described in claim 11 is directed to the image display method described in claim 9 or claim 10, wherein

The monochrome image data

R image data = KRX B image data (0 <KR <1)

G image data = KG X B image data (0 <KG <1)

[0020] The invention according to claim 12 is the image display method according to claim 11, wherein at least one of the KR and KG is a range of at least the luminance LO and the luminance L1. The lower the brightness, the smaller the value.

[0021] The invention according to claim 13 is the image display method according to claim 11 or claim 12, wherein the KR and KG are at least the luminance LO and the luminance described above. Within the range of L1, KR and KG. [0022] The invention according to claim 14 is the image display method according to claim 9, wherein the control unit converts the monochrome image data into coordinates (CIE chromaticity diagram). X, y) is characterized in that at least one of the coordinates x and y is distributed so as to decrease at least within the range of the luminance LO and the luminance L1.

[0023] The invention according to claim 15 is the image display method according to any one of claims 9 to 14, when a desired color tone is input. The monochrome image data is distributed to the RGB image data in accordance with the input color tone.

[0024] The invention according to claim 16 is the image display method according to any one of claims 9 to 14, wherein V is a deviation. When an observer identification code that can identify an observer is input, the monochrome image data is distributed to the RGB image data according to a desired color tone associated with each observer. And

The invention described in claim 17 is characterized in that it causes a computer to execute the image display method described in any one of claims 16 and 16 in claim 9 as well.

[0025] According to the invention described in claim 1 and claim 9, an RGB image having an appropriate chromaticity close to the color tone of a blue-based film from monochrome image data. Since it is distributed to data, it is displayed on the color display section of the liquid crystal panel etc. in a display form (characteristic) suitable for diagnosis with little sensory discomfort between the film color tone and the color tone of the monitor screen for the doctor who is the observer It becomes possible. In addition, doctors and the like can sufficiently identify the diseased part on the monitor screen, and it is possible to detect the lesion appropriately.

[0026] According to the invention described in claim 2 and claim 10, the range of maximum brightness LO and 1/30 brightness L1 when displaying an image is within the range of human Because the eye has a density range (luminance range) that is particularly sensitive to differences in color tone, at least in this density range (luminance range), the tone is adjusted to make the display more suitable for diagnosis. There is an effect that makes possible. [0027] According to the invention described in claim 3 and claim 11, an RGB image having an appropriate chromaticity close to the color tone of a blue-based film from monochrome image data. Since it is distributed to the data, it can be displayed on the color display unit in a display form (characteristics) suitable for diagnosis with little sensory discomfort between the color tone of the film and the color tone of the monitor screen. Become. In addition, the doctor and the like can sufficiently identify the lesion site on the monitor screen and the doctor or the like on the monitor screen, so that it is possible to appropriately detect the lesion.

[0028] According to the invention described in claim 4 and claim 12, an RGB image having an appropriate chromaticity close to the color tone of a blue-based film from monochrome image data. Since it is distributed to the data, it can be displayed on the color display unit in a display form (characteristics) suitable for diagnosis with little sensory discomfort between the color tone of the film and the color tone of the monitor screen. Become. In addition, it is possible for doctors and the like to sufficiently identify the lesion site on the monitor screen, and to detect the lesion appropriately.

[0029] According to the invention described in claim 5 and claim 13, an RGB image having an appropriate chromaticity close to the color tone of a blue base film from monochrome image data. Since it is distributed to the data, it can be displayed on the color display unit in a display form (characteristics) suitable for diagnosis with little sensory discomfort between the color tone of the film and the color tone of the monitor screen. Become. In addition, it is possible for doctors and the like to sufficiently identify the lesion site on the monitor screen, and to detect the lesion appropriately.

[0030] According to the invention described in claim 6 and claim 14, an RGB image having an appropriate chromaticity close to the color tone of a blue-based film from monochrome image data. Since it is distributed to the data, it can be displayed on the color display unit in a display form (characteristics) suitable for diagnosis with little sensory discomfort between the color tone of the film and the color tone of the monitor screen. Become. In addition, it is possible for doctors and the like to sufficiently identify the lesion site on the monitor screen, and to detect the lesion appropriately.

[0031] According to the invention described in claims 7 and 15, there are various color tones depending on the type of film, and the color tone and preference of the film used by the doctor who is an observer. Even if the color tone of the film is different, enter the desired color tone and based on this Since it is distributed to RGB image data, it is possible to display an image with a color tone that suits the viewer's preference on the monitor screen.

[0032] According to the inventions described in claims 8 and 16, there are various color tones depending on the type of film, and the color tone and preference of the film used by the doctor who is an observer. Even if the color tone of the film is different, the viewer identification code associated with the desired color tone is input, and based on this, it is distributed to the RGB image data of the desired color tone for each observer. The effect is that an image with a color tone that suits the viewer's preference can be displayed on the monitor screen.

[0033] According to the invention described in claim 17, it is possible to cause a computer to execute the image display method described in any one of claims 16 in the claim 9. There is an effect that can.

Brief Description of Drawings

FIG. 1 is a diagram showing a schematic configuration of an image display device according to the present invention.

FIG. 2 is a block diagram showing a control configuration of the image display apparatus according to the present invention.

FIG. 3 is a diagram showing image data distribution of the image display device according to the present invention.

FIG. 4 is a timing chart showing an example of image data processing of the image display device according to the present invention.

FIG. 5 is an xy chromaticity diagram when film A is used in the image display device according to the present invention.

FIG. 6 is an xy chromaticity diagram when film B is used in the image display device according to the present invention.

FIG. 7 is an xy chromaticity diagram when film C is used in the image display device according to the present invention.

FIG. 8 is an xy chromaticity diagram when film D is used in the image display device according to the present invention.

FIG. 9 is an xy chromaticity diagram when film E is used in the image display device according to the present invention.

FIG. 10 is a diagram showing the relationship between the input data according to the present invention and the values of KR and KG for reproducing the color tone of the monochrome film using the input data.

FIG. 11 is a block diagram showing a schematic configuration of a modification of the image display device shown in FIG. 1.

12 is a block diagram showing a schematic configuration of a modified example of the image display device shown in FIG. Explanation of symbols

[0035] Single image display device 2 LCD panel

3 knock lights

4 Image supply device

5 interface

6 Control unit

7 First frame memory

8 Data processing section

9 Second frame memory

10 frame switching section

11 LCD driver

21 color tone input means

22, 24 Memory

23 Observer identification code input means

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the image display device according to the present invention will be described. However, the scope of the invention is not limited to the illustrated examples.

FIG. 1 shows a schematic configuration of an image display device 1 according to the present invention. This image display device 1 has a maximum display brightness of 200 so that it can be used as a medical image display device.

Preferably ~ 5000cd / m2! / ,.

As shown in FIG. 1, the image display device 1 includes a color liquid crystal panel composed of liquid crystals.

2 is provided, and an image is displayed on the liquid crystal panel 2. As the liquid crystal panel 2, all known liquid crystal panels can be used. In addition, the operation mode of the LCD panel 2 is not particularly limited. TN (Twisted Nematic) mode, STN (Super

Various operation modes such as Twisted Nematic mode and MVA (Multi-domain Vertical Alignement) mode can be applied.

The liquid crystal panel 2 is provided with a backlight 3 that irradiates light on the back surface of the liquid crystal panel 2 in order to observe an image displayed on the liquid crystal panel 2. A known liquid crystal panel backlight can be applied to the backlight 3. [0040] The image display device 1 is connected to an image supply device 4 of a medical diagnostic device via an interface 5, and image data of a monochrome diagnostic image acquired by the medical diagnostic device is stored. The image is input to the image display device 1. As this medical diagnostic device

, CR (Computed Radiography) X-ray diagnostic equipment, MRI (Magnetic Resonance Imaging) diagnostic equipment, and various CT (Computed Tomography) computed medical equipment Possible force The image supply device 4 is not limited to the one exemplified here, but may be an image storage device such as an image server connected by a network.

[0041] The interface 5 is connected to a control unit 6 that controls each unit of the image display device 1. Further, the control unit 6 converts the image data supplied from the image supply device 4 into image data to be displayed on the image display device 1 for FRC (Flame Rate Control).

Here, FRC display means that when displaying high-resolution image data with a gradation resolution (number of bits) using a display device, the number of images corresponding to the difference in the number of bits from the image data with a high number of bits. By generating an image data group with a low number of bits and displaying the image data group in sequence, gradation representation corresponding to a high number of bits is performed on an image display device with a low number of bits. is there.

Specifically, the data processing unit 8 generates 2n image data groups with a low bit number when the number of bits is different, stores the generated image data groups in a frame, and sequentially displays them. Therefore, a normal image display device is used because it has lower gradation resolution of image data than a medical diagnostic device.

FIG. 2 shows the configuration of the control unit 6. In the present embodiment, the 10-bit image data acquired by the image supply device 4 is divided into four to obtain 8-bit image data, and the obtained 8-bit image data is used in four frames. By displaying them sequentially, 8 bits represent 10 bits of gradation. This will be described in detail below with reference to FIG.

The control unit 6 is provided with a first frame memory (referred to as FM in the figure) 7 for storing 10-bit image data input from the interface 5. This first frame memo A data processing unit 8 that divides 10-bit image data input from the interface 5 into 8-bit image data is connected to the line 7.

In addition, the data processing unit 8 distributes monochrome image data input from the image supply device 4 to RGB (R: Red, G: Green, B: Blue) three-color image data. Yes. Specifically, the data processing unit 8 converts the input monochrome image data.

B image data = monochrome image data

R image data = KR X B image data (rounded down) (0 <KR <1) G image data = KG X B image data (rounded down) (0 <KG <1) · · · Formula (1)

To be distributed.

[0046] The data processing unit is connected to a second frame memory 9a to a second frame memory 9d for storing the RGB image data distributed according to the equation (1). Specifically, each of the RGB data distributed by the equation (1) is transmitted by the data processing unit 8 according to the data distribution stored in the data processing unit 8 (shown in FIG. 3). It is allocated to 2 frame memory 9d. For example, as shown in FIG. 4, the data processing unit 8 distributes 10-bit RGB data 509 to 128, 127, 127, and 127 image data, and each image data is assigned to the second frame memory 9a to the second frame memory 9a. It is stored in the frame memory 9d. Similarly, the RGB data 510 is divided into 128, 127, 128, and 127 image data, and each image data is stored in the second frame memory 9a to the second frame memory 9d. It is like that.

[0047] The frame switching unit 10 is connected to the second frame memory 9a to the second frame memory 9d. Connected to the frame switching unit 10 is a liquid crystal driving unit 11 for outputting image data stored in the second frame memory 9a to the second frame memory 9d! Speak. The liquid crystal driving unit 11 is connected to the liquid crystal panel 2, and the liquid crystal driving unit 11 controls the liquid crystal panel 2 based on the image data to display an image.

[0048] FIGS. 5 to 9 show the relationship between luminance and color tone when images recorded from blue-based monochrome film A to monochrome film E are displayed on the shukasten. These coordinates (X, y) in Fig. 5 to Fig. 9 are the coordinates of CIE chromaticity. The smaller the x and y values, the more blue the color becomes. Indicates strong. The arrows in the figure indicate the direction in which the color tone changes when the brightness is changed from high to low (when the film density is changed from light to dark). In addition, two types of fluorescent lamps with different colors are used as light sources for Schaukasten.

As shown in FIG. 5, the relationship between the luminance and the color tone of the monochrome film A is such that the blue color tone becomes stronger as the luminance becomes lower. In addition, as shown in FIGS. 6 to 9, the monochrome film B force monochrome film E has a tendency that the color tone of the bluish color becomes stronger as the luminance decreases in a part of the luminance range. The tendency of the change in color tone with respect to the brightness shows the same tendency in each film even if the type of light source is different.

FIG. 10 shows the relationship between the input data and the values of KR and KG that reproduce the color tone of the monochrome film using the input data. Figures 10 (a) to 10 (e) correspond to monochrome film A to monochrome film E, respectively. This input data indicates the display brightness. The larger the X-axis, the higher the display brightness. Therefore, the arrows shown in FIGS. 5 to 9 indicate the direction in which the value of X decreases in FIG.

[0051] As shown in FIG. 10, the values of KR and KG tend to be smaller as the luminance is lower. In addition, as shown in Fig. 10, the value of KG tends to be larger than the value of KR, and at least within the range of the maximum luminance and 1/30 of the luminance, The value of KG is larger than the value.

Next, the operation of the image display device 1 using the method according to the present embodiment will be described.

When the image supply device 4 inputs image data to the control unit 6 via the interface 5, the control unit 6 stores the image data in the first frame memory 7.

[0054] The control unit 6 distributes the image data input to the data processing unit 8 to each of the RGB image data according to the equation (1), and displays the allocated image data in the data of Table 1 (Fig. 3). The second frame memory a9 to the second frame memory al2 are stored according to the distribution.

[0055] The frame switching unit 10 switches the connection between the second frame memory a9 to the second frame memory al 2 by the drive control of the control unit 6, and is stored in the second frame memory a9 to the second frame memory al2. The image data is output to the liquid crystal drive unit 11. The liquid crystal drive unit 11 Based on the image data input to the crystal drive unit 11, the liquid crystal panel 2 is driven and controlled to display an image on the liquid crystal panel 2.

[0056] As described above, the image display device 1 has an effect of being able to display a monochrome image in a blue color tone more suitable for diagnosis.

[0057] In this embodiment, in order to realize a color tone suitable for displaying an image on a blue-based monochrome film, the distribution ratio of the image data is determined by the equation (1). The realization of the color tone shown in the example is not limited to this.

[0058] For example, the input monochrome image data

B image data = monochrome image data Z4 (rounded down)

When displaying with 8-bit gradation resolution, FRC display is not performed, so the same display image data is stored in each frame memory 9a, 9b, 9c, 9d. You can display it with bit gradation resolution.

Further, for example, as shown in FIG. 11, a color tone input means 21 for an observer (physician or the like) to set and input a desired color tone to the image display device, and a monochrome image data for realizing each color tone. It is also possible to provide a storage unit 22 that stores in association with what ratio data is distributed to RGB. In this case, for example, the storage unit 22 can store the values of KR and KG corresponding to the input signal input from the color tone input means 21 as a table (Look Up Table: LUT) (not shown). For example, a plurality of KR and KG LUTs corresponding to the color tones of a plurality of films can be stored. Further, the color tone input means 21 may display, for example, a plurality of film type names, and the color tone may be input by the viewer selecting a desired film type name from among them. A color tone may be displayed, and an observer may select a desired color tone from the displayed color tone. When a desired color tone is input from the color tone input unit 21, the control unit 6 reads a table corresponding to the color tone from the storage unit 22, and the data processing unit 8 allocates data while referring to this, and displays the display image. Image data is generated. [0060] By adopting a configuration in which the observer can input a desired color tone in this way, the type of film conventionally used in a medical facility and the color tone of the film used and familiarized by the observer are known. Since the color tone of the image displayed on the liquid crystal panel 2 can be changed according to the desired color tone, an image with less sense of incongruity can be obtained and appropriate diagnosis can be performed.

Furthermore, when an observer identification code such as an observer ID that can identify an individual is assigned to each observer (doctor or the like), for example, as shown in FIG. An observer identification code input means 23 and a storage unit 24 may be provided for an observer (such as a doctor) to input an observer identification code. In this case, for example, the observer's favorite color tone is associated with the observer identification code and stored in the storage unit 24 in advance. When the observer identification code is input from the observer identification code input means 23, the control unit 6 reads out the color tone associated with the input observer identification code from the storage unit 24, and the data processing unit 8 The color tone is automatically selected, and the data is distributed so as to obtain this color tone, thereby generating display image data.

[0062] By adopting a configuration in which a desired color tone is automatically selected when the observer inputs the observer identification code in this way, the type of film and the observer that have been conventionally used in medical facilities. However, the color tone of the image displayed on the liquid crystal panel 2 can be changed according to the color tone of the film and the color tone of your choice. Because the color tone of the film you are familiar with varies depending on the observer, it is convenient to change the color tone for each observer without entering any special settings by entering the observer identification code. Therefore, it is possible to easily obtain an image with less sense of incongruity and perform an appropriate diagnosis.

In FIG. 11 and FIG. 12, the color tone input means 21 or the observer identification code input means 23 and the storage units 22 and 24 are integrally provided inside the image display device provided with the liquid crystal panel 2. However, it may be possible to provide all or a part of these to an external device such as an image supply device.

In addition, it goes without saying that the present invention is not limited to the above embodiment and can be modified as appropriate.

Claims

The scope of the claims

[1] A control unit that distributes monochrome image data to RGB image data,

The control unit distributes the monochrome image data to the RGB image data so that the lower the luminance is, the stronger the blue color tone is.

[2] In the range of at least the maximum luminance LO when displaying the monochrome image data and the luminance L1 that is 1/30 of the maximum luminance LO, the control unit reduces the blue color as the luminance decreases. 2. The image display device according to claim 1, wherein the monochrome image data is distributed to RGB image data so as to enhance color tone.

[3] The control unit stores the monochrome image data.

R image data = KRX B image data (0 <KR <1)

G image data = KG X B image data (0 <KG <1)

The image display device according to claim 1 or 2, wherein at least one of KR and KG takes a smaller value as the luminance is lower. .

[4] At least one of the KR and KG takes a smaller value as the luminance is lower, at least within the range of the luminance LO and the luminance L1. The image display device according to item.

[5] The KR and KG are K at least within the range of the luminance LO and the luminance L1.

5. The image display device according to claim 3 or claim 4, wherein R <KG.

[6] When the monochrome image data is represented by coordinates (x, y) on the CIE chromaticity diagram, the control unit has the coordinates x, y at least within the range of the luminance LO and the luminance L1. 2. The image display device according to claim 1, wherein at least one of them is distributed so as to decrease.

[7] A color tone input means for inputting a desired color tone is provided.

The control unit is configured to output the monochrome image according to a color tone input by the color tone input unit. The image display device according to any one of claims 1 to 6, wherein image data is distributed to the RGB image data.

[8] An observer identification code input means for inputting an observer identification code that can identify the observer, and a storage unit that stores the observer identification code and a desired color tone for each observer in association with each other. Prepared,

The control unit distributes the monochrome image data to the RGB image data according to a desired color tone of an observer corresponding to an observer identification code input by the observer identification code input unit. The image display device according to any one of claims 6 to 6, wherein the force is the first power of the range.

[9] Based on the RGB image data generated by distributing the monochrome image data, the image display method to display the color image,

An image display method characterized by allocating the monochrome image data to the RGB image data so that a blue color tone becomes stronger as the luminance is lower.

[10] At least within the range of the maximum luminance LO when displaying the monochrome image data and the luminance L1 that is 1/30 of the maximum luminance LO, the lower the luminance, the stronger the blue tone. The image display method according to claim 9, wherein monochrome image data is distributed to RGB image data.

[11] The monochrome image data

R image data = KRX B image data (0 <KR <1)

G image data = KG X B image data (0 <KG <1)

11. The image display method according to claim 9, wherein at least one of KR and KG takes a smaller value as the luminance is lower.

12. At least one of the KR or KG takes a smaller value as the luminance is lower, at least within the range of the luminance L0 and the luminance L1, according to claim 11, Image display method.

[13] The range of claim 11 or claim 12, wherein the KR and KG are KR and KG at least within the range of the brightness L0 and the brightness L1. Image display method.

[14] When the monochrome image data is expressed by coordinates (X, y) on the CIE chromaticity diagram, the control unit has the coordinates x and y at least within the range of the luminance LO and the luminance L1. 10. The image display method according to claim 9, wherein at least one of them is allocated so as to decrease.

[15] When a desired color tone is input, the monochrome image data is distributed to the RGB image data according to the input color tone. The image display method according to any one of the above items.

[16] When an observer identification code capable of identifying an observer is input, the monochrome image data is distributed to the RGB image data according to a desired color tone associated with each observer. The image display method according to any one of claims 14 to 14, wherein the ninth term force in the claim is characterized.

[17] An image processing program for causing a computer to execute the image display method according to any one of claims 9 to 16.