3 Mega-Pixel with ISD Technology 21.3" Digital Mammography Display. (Model: MS31i2)

3 Mega-Pixel with ISD Technology 21.3" Digital Mammography Display. (Model: MS31i2)

3 Mega-Pixel with ISD Technology 21.3" Digital Mammography Display. (Model: MS31i2)

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3MP-based Display for Digital Mammography
Digital mammography viewing demands an extraordinarily high level of precision from your LCD display. Totoku's MS31i2 redefines new standards of care by over-delivering resolution and clarity for improved accuracy in breast cancer screening.
With integrated ISD (Independent Sub-pixel Drive) technology, the MS31i2 exceeds resolution values of traditional 5 Mega-pixel displays, and due to economies of scale, is more affordable than its 5 megapixel counterpart. Introducing the MS31i2, with ISD technology enables a 3Mega-pixel-based LCD to render 9 mega sub-pixel images, exceeding the current standards of care for primary mammography diagnosis. The MS31i2 is FDA (510K) cleared for the use of Digital Mammography.


High resolution of 9M sub-pixels realized by ISD technology

Faithful Reproduction of Image Details
While a pixel pitch of 3MP display is 210µm, MS31i2 achieves 70µm in sub-pixel chain direction by newly developed ISD technology to realize excellent depiction of image details.

Advanced Image Quality with Less Degradation
To display an overall image whose native resolution is higher than the monitor is able to reproduce, the image is converted to a lower resolution image with a certain amount of data loss.
The MS31i2 with high resolution offers excellent image reproduction, faithful to the original captured by the modality device with less image degradation.

ISD (Independent Sub-pixel Drive) Technology
Driven by each sub-pixel value corresponding to detailed information recorded in an original image, three times resolution enhancement is achieved. (Patent pending) In addition, up to 1276 shades of gray are now simultaneously displayable by the upgraded ISD technology.
*Customized viewer software is required to display images with enhanced resolution by the ISD technology.

ISD Technology
As imaging technology advances, modality devices are reproducing such high resolution that even current 5MP displays are unable to reproduce, creating a bottleneck in softcopy diagnostic environment. ISD (Independent Sub-pixels Drive) technology* to accept higher resolution output from modality devices as a major breakthrough. *Patent pending
*Customized viewer software is required to display images with enhanced resolution by the ISD technology.

  • Pixel pitch of one-third in horizontal direction (the sub-pixel chain direction) actualizes the accurate depiction of the images.
  • The faithful image depiction to its original with less image degradation is realized.
  • Image quality is significantly improved without changing the pixel structure of conventional displays, and it does not have any adverse impact on luminance and contrast characteristics.
  • Simultaneous display of 1276 shades of gray
Log-awaited resolution enhancement of displays:
Resolution of modality devices has already achieved a pixel size of approximately 25 to 100μm and a pixel number of 4 to 67 mega-pixels (MP). However, even 5MP displays with 165μm that can provide the current maximum resolution, still do not have enough resolution properties to meet the modality devices’ resolution.

Table1 Resolution of major mammo systems and a 5MP display

Mammo system
Pixel size(μm)
Resolution (ピクセル)
3540 × 4740  16.77MP
7080 × 9480  67.12MP
1914 × 2294  4.39MP
2560 × 3328  8.52MP
5MP Display
2048 × 2560  5.24MP

When an image is captured by a modality device, most times the native resolution is higher than the monitor is able to reproduce. Consequently, either the overall image is converted to a lowerresolution image with reduced quality, which is executed by viewer software (sub-sampling processing) or only a portion of the image is depicted with the original resolution. Fig.1 shows that the overall image is depicted on the display by only 31% of the information contained in the original image.

Fig.1 Depiction image when an original image consists of more pixels than
a display in full-screen. It is reduced to only 31% of the original.

Independent Sub-pixel Drive (ISD) technology:
A monochrome display has a large number of pixel elements and each pixel element consists of three sub-pixels, which are driven as one pixel in conventional monochrome displays. Newly developed technology, Independent Sub-pixel Drive (ISD) composed of a display that comes with the ISD algorithm and special viewer software enables each sub pixel to be driven independently, and consequently MS51i2 provides superior, lossless image reproduction.

Fig. 2 shows mechanism of resolution enhancement by the ISD and comparison of captured images on a conventional display and a display with ISD technology. By the ISD function, the image is depicted more accurately.

Fig.2 Mechanism of ISD and comparison of the images of three fine lines

Improvement of image quality:

Fig. 3 and 4 show captured images on a conventional 5MP LCD and MS51i2 that was developed out of a conventional 5MP LCD with ISD technology. The depiction detail was grately improved on MS51i2 and Fig. 4 shows its excellent depiction ability of the micro calcifications, especially the edges.

Fig. 5 shows the comparison of measured MTFs of the conventional 5MP LCD and the MS51i2 that employ the same LCD panels of 5MP. As shown in the graph, the MTF of MS51i2 was improved obviously by the ISD function.

Furthermore, comparative evaluations performed by radiologists substantiated the clinical benefits of the MS51i2 over the conventional 5MP LCD.


While image quality of the medical displays such as luminance, contrast, viewing angle, and grayscale features has been improved, resolution enhancement was not actualized because of its cost.
From the physical measurements and perceptual comparisons, this new resolution enhancement technology by the ISD, which actualizes excellent depiction ability inexpensively, would be very important in softcopy diagnostic environment.

3MP-based display with the ISD technology performs either equaling or surpassing the 5MP's

Comparison between 9 MsP and 5 MP

Visibility comparison
Visibility comparison of existence and shape evaluation of microcalcifications (MCLs),
using 50 clinical cases obtained by a digital mammography system (pixel size: 70um).
Scoring method for 9MsP superiority

Visibility comparison
The most of cases were rated as "Equivalent", and 23% were answered as "Better". Our study indicated that the potential performance of the 9MsP LCD was equivalent to or better than the conventional 5MP LCD for evaluating very small MCLs and interpreting clinical digital mammography with various types of MCLs.

Display magnification % was adjusted freely by each observer.

Comparative Study between 9 Mega-sub-Pixel and 5 Mega-Pixel LCDs using Simulated Microcalcification images and Clinical Mammograhy (RSNA2009)
Katsuhiro Ichikawa Ph. D1), Hiroko Kawashima, MD 1), Aya Nishimura 2), Mikio Hasegawa 3), Naohiro Kimura 3)
1) Institute of Medical, Pharmaceutical and Health Sciences, Kanazawa University, 2) Kanazawa University, hospital, 3) TOTOKU Electric Co., Ltd.

Visual Detection study using images of 0.15mm simulated microcalcification
This chart shows relationship magnifications and dectablility for the 9MsP and the 5MP's where the 9MsP exceeds 5MP in detectability.


Title: Clinical Usefulness of Super High-Resolution Liquid Crystal Displays Using Independent Sub-pixel Driving Technology International Workshop on Digital Mammography (IWDM) 2008 August 2008, THE UNIVERSITY OF ARIZONA, U.S.A
Katsuhiro Ichikawa 1), Hiroko Kawashima 2), Naohiro Kimura 3), and Mikio Hasegawa 3)
1) Graduate School of Medical Science, Kanazawa University, 2) Department of Radiology, Kanazawa University Hospital, 3) Totoku Electric Co., Ltd.

Special AR Coating

The special Anti-Reflection (AR) coating is a surfacetreatment that provides AR layers directly on a LCD panel as shown in Table 1.
Fig. 1 shows comparison of micro bright points displayed on the special AR-coated LCD and the AG-coated LCD. Due to the reduced diffused reflection by the special AR coating, the bright point is displayed more clearly with the improved focus and contrast compared to the one on the AG-coated LCD.

Fig.1 Illustration of the displayed micro bright points

Physical measurement results of the display properties
Table 2 shows physical measurement results of the display properties. The special AR-coating obtained the best results in the three surface treatments for all the measurement items except for the specular reflection (Rs).
Table2 Measurement results in each surface treatment
Max. luminance
(Dark room)
Min. luminance
(Lighted room)
Contrast ratio
Reflection coefficient
*Viewing angle (Left - Right)
Dark room
Lighted room
Rs (Specular)
Rd (Diffuse)
AR coating
AG + AR filter

AG coating

• A 3MP display was used in the measurement
• The measurement was performed in a relative manner where AG + AR filter is 100.
   (The bigger values indicate the better properties.)
*The viewing angle was measured in accordance with AAPM TG18.
   (The specified viewing angles indicate where the contrast ratio of over 170 is achieved.)

Fig.2 Noise characteristics (NPS characteristics)
The noise level of the special AR coating is lower than the AG coating.

Fig.3 Focus (MTF characteristics)
The special AR coating achieved the higher focus properties than the AG coating.

Specular reflection characteristics
Fig. 4 shows photographs of each LCD with 4 different surface treatments reflecting the background in the lighted room. Fig. 5 shows image analysis of the photographs in Fig. 4. The X-axis represents the horizontal direction in the photographs and the Y-axis represents relative luminance.
A piece of white paper was placed in front of the surface of each LCD panel to take a photo of its appearance on the screen by reflection.
Although the paper edge appears more clearly on the special AR-coated LCD than the AG-coated LCD or the AG-coated LCD with the AR filter, as shown in Fig. 5, relative luminance of the special AR-coated LCD is lowest. Conversely, the white paper appears most clearly on the mirror-shiny surface of the *Glare type LCD, and its relative luminance is the highest of all LCDs.
*Non-AG-coated LCD panel to improve the noise and the focus properties.

Fig.4 Comparison of the background reflected on the screen in the lighted room

Fig. 5 Graph of the photograph analysis

The special AR-coating obtained the best results in the three surface treatments for all the testing items except for the specular reflection (Rs). Although the reflection coefficient in the specular reflection is slightly lower than the others, as shown in Fig. , the special AR-coated LCD achieves the lowest relative luminance of the reflected image.
For these reasons, it was indicated that the special AR-coating is the surface treatment best suited for medical displays.

Simultaneous display of 1276 shades of gray Simultaneous display of 1276 shades of gray
Realizes smoother grayscale display required for medical image displays.

Newly developed luminance stabilizing system λ-Sentinel II New luminance stabilizing system λ-Sentinel II
λ-Sentinel II consists of a luminance sensor and luminance control circuit. The luminance sensor, integrated into the front bezel, consistently monitors and accurately stabilizes luminance on the screen by rapidly communicating with the backlight sensor.
In addition, a build-in luminance sensor provided with i2 models enables even simpler calibration without attaching the calibration sensor.

Luminance stabilizing system to provides continuous stable display for medical images

A change in luminance affects gamma characteristics and therefore has adverse effects on diagnostic imaging. TOTOKU'smedical image displays are equipped with a luminance stabilizing system that automatically compensates for luminance changes due to startup drift, temperature change, and aging.

Luminance stabilizing system λ-Sentinel

λ-Sentinel II Luminance stabilizing system λ-Sentinel II

λ-Sentinel II consists of a luminance sensor and a luminance control circuit. The luminance sensor attached in front of the screen constantly monitors and accurately stabilizes luminance on the screen surface by sending feedback to the control circuit.

Newly developed luminance stabilizing system λ-Sentinel IILuminance sensor
  • With luminance fluctuation caused by the LCD module taken into account, highly accurate luminance control is achieved.
  • Actual luminance measurements including intermediate luminance are taken on the screen surface.
  • Build-in luminance sensor provided with i2 models enables even simpler calibration without attaching the calibration sensor.

Note: λ-Sentinel II module is built into the the ME/CCL Series i model displays. Other models are equipped with λ-Sentinel (TOTOKU's conventional system).

Remote grayscale check and remote calibration functions
Conformance testing to DICOM GSDF and calibration can be remotely accomplished. These features minimize the burden on display administrators.
* Optional PM Medivisor software is required.

Auto remoto grayscale conformance evaluation
Combined with TOTOKU’s performance monitoring software PM Medivisor, grayscale conformance to DICOM according to AAPM TG18 can be checked automatically and remotely.

  • PM Medivisor’s scheduling function activates periodic auto-evaluation.
  • The test runs as a background process. Thus it can be carried out even when the display is in use.
  • Results are available graphically for easy review and are centrally managed by PM Medivisor.

Remote calibration capability
The remote calibration feature is added to reduce the burden on system administrators. Calibration of remote displays canbe accomplished from a management terminal.

  • Execution of calibration using the built-in luminance sensor.
  • Results are centrally managed by PM Medivisor.

* Remote calibration is available when "i2 model" is used along with PM Medvisor Ver. 4.0 and above.

Luminance equalizer λ-Uniformity Congruence) Luminance equalizer λ-Uniformity Congruence
Is built in to achieve highly accurate luminance uniformity across the screen. Luminance unevenness is minimized in the final tune-up prior to shipping.
* Images shown are for illustrative purposes only.

Calibrates luminance and gamma to enable smooth grayscale display that is faithful to DICOM GSDF.Calibration function
Calibrates luminance and gamma to enable smooth grayscale display that is faithful to DICOM GSDF.
* Optional calibration kit is required.

Calibration function to accurately adjust gamma, color temperature, and luminance
Medical image displays are commonly required to display grayscale according to the Grayscale Standard Display Function (GSDF) defined by DICOM Part 14. The calibration function creates the optimum conditions for a medical imaging display by adjusting luminance levels, color temperature, and grayscale characteristics to achieve DICOM GSDF compliant grayscale output.

Models supported: All ME/CCL Series models, except ME183L and CCL192 plus
Note: Calibration requires an optional calibration kit*

How it works
The calibration function corrects the driving level of the LUT (Look-up Table), a memory that specifies the LCD driving, and writes it in the LUT. In other words, calibration adjusts grayscale characteristics, color temperature (color displays only), and luminance.

The luminance for each driving level is corrected such that the resulting curve matches the DICOM GSDF achieving smooth grayscale output.

The luminance for each driving level is corrected such that the resulting curve match the DICOM GSDF and smooth grayscale is achieved.

Graph is for explanatory purpose only.

* Calibration kit (optional)
Package contents
  • Calibration software: Medivisor for i2 Series, Medivisor Grayscale, Medivisor Color, Medivisor for ME201L/ME181L
  • QA Medivisor
  • Utility Software for i2 Series
  • GSDF Checker
  • Luminance sensor

Hardware based pivot function to enable high speed drawing in portrait orientation
The pivot function allows for a 90-degree rotation of the LCD panel into portrait orientation. Unlike other pivoting functions that are implemented using graphics cards and/or that require special software, TOTOKU's hardware pivot function is directly implemented in display hardware, and thus it is much faster with less noise.

OSD Information Display
OSD Information Display

With a push of a button, the display's current status can be checked such as the display model, total operating time, actual measurement of luminance, and calibration settings.

LED indicator to inform of current statusLED indicator to inform of current status
A glance at the LED indicator tells you the display's current operating status in three distinct colors. When in normal mode (luminance is stabilized), the LED is not lighted to minimize negatively impacting the diagnostic interpretation.

LED Indicator to inform of current status
Models supported All i2 and i models

Enhanced convenience with utility software:
Advanced power saving*

The backlight dims as the screensaver starts, reducing power consumption and preventing unnecessary deterioration of the backlight.
* This feature may not be available, depending on the specifications of the graphics card used.

Gamma check
18 points of luminance values are measured and plotted into a graph.
Ambient light and display luminance measurement
The built-in sensors measure display luminance and ambient illuminance.

Pairing service to match display colors (Optional)
Due to the variation in colors among cold cathode fluorescent lamps (CCFL) used as backlights, slight differences in color tone between displays are unavoidable. Medical imaging often uses two displays side-by-side, and it is very important that they present
TOTOKU offers a display pairing service that match colors of two displays using a high-definition spectrophotometer before shipping.

Models supported: All monochrome medical image displays

* Consult your dealer for more information about the pairing service.

Pairing service to match colors of displays

Worldwide medical safety standards Worldwide medical safety standards
This display is certified under various medical safety standards that are much more demanding than those for general-purpose IT equipment.


Model Name MS31i2
LCD Panel Technology 21.3-inch, Monochrome, TFT active matrix IPS Technology
Display Area 433mm x 325mm
Pixel Pitch 0.2115mm x 0.2115mm
Contrast Ratio 900:1 (typ)
Maximum Luminance 1450cd/m² (typ), (calibrated to 410cd/m²)
Viewing Angle 170° horizontal and vertical (typ)
Visual Performance Available Resolution 1536 X 2048, ISD ON: 1536 X 6144(sub-pixel)
*MS31i2 supports 9M-ISD and 3M-normal modes.
To use MS31i2 in 9M-ISD mode, customized viewer software is required.
Grayscale 3061 shades of gray to 256 shades of gray
Simultaneous display of 1276 shades of gray is possible with the customized viewer.
Input Signal Input Sync Signal DVI 1.0 compliant
Plug and Play DDC2B compliant
Input Power Supply Input AC Adapter 100V-240V (±10%) 50/60Hz
Maximum Power Consumption 95W (typ), (with power management feature)
Features Calibration Control Luminance, Gamma, Capability of saving 3 sets of LUT settings (An optional calibration kit is required.)
OSD Information Display Model name, Serial No., Total operating time, Calibration settings (Operating time from Last Calibration, Luminance, Gamma, etc.), Current luminance, etc.
USB Hub USB Rev. 2.0 compliant, Self-powered
USB upstream connector (x1), USB downstream connector (x2)
Other Features Luminance Uniformity Correction Function, Hardware Pivot function, LED indicator
Standards UL60601-1, CSA C22.2 No. 601.1, MDD/CE, FCC-B, VCCI-B , FDA510(k)
Physical Characteristics Dimensions (WxHxD) Landscape : 474.0 (W) X 468.4 / 529.9 (H) X 220.0 (D) mm
Portrait : 367.0 (W) X 521.9 / 583.4 (H) X 220.0 (D) mm
Weight Net: approx. 11.2kg, Without tiltstand: approx. 7.0kg
Tilt Stand Tilt, Swivel, Portrait / Landscape
Mount 100mm VESA compliant
Security Slot On the back of the panel and the tilt stand
LCD surface treatment Special AR coating
Accessories AC adapter, Power cord (3P), DVI cable, USB cable, User manual