Healthcare

Independent Sub pixel Drive Technology

As imaging technology advances, modality devices are reproducing such high resolution that even current 5MP monitors are unable to reproduce, creating a bottleneck in softcopy diagnostic environment. Independent Sub pixels Drive technology* to accept higher resolution output from modality devices as a major breakthrough.

 

*Patented

*Customized viewer software is required to display images with enhanced resolution by the Independent Sub pixel Drive technology.

 

Features

  • 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 monitors, and it does not have any adverse impact on luminance and contrast characteristics.
  • Simultaneous display of 1276 shades of gray

Long-awaited resolution enhancement of monitors

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 Monitors 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 Monitor

Mammo system Pixel size(μm) Resolution
A 50 3540 x 4740 (16.77MP)
B 25 7080 x 9480 (67.12MP)
C 100 1914 x 2294 (4.39MP)
D 70 2560 x 3328 (8.52MP)
5MP Monitor 165 2048 x 2560 (5.24MP)

When an image is captured by a modality device, most times the native resolution is higher than the resolution that monitor is able to reproduce. Consequently, either the overall image is converted to a lower resolution 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 monitor 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 monitor in full-screen. It is reduced to only 31% of the original.


Independent Sub pixel Drive technology

A monochrome monitor 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 monitors. The technology we developed, Independent Sub pixel Drive composed of a monitor that comes with the Independent Sub pixel Drive algorithm and special viewer software enables each sub pixel to be driven independently, and consequently the monitor provides superior, lossless image reproduction.

 

Fig. 2 shows mechanism of resolution enhancement by the Independent Sub pixel Drive and comparison of captured images on a conventional monitor and a monitor with Independent Sub pixel Drive technology. By the Independent Sub pixel Drive function, the image is depicted more accurately.

Fig.2 Mechanism of Independent Sub pixel Drive 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 MS-S500 that was developed out of a conventional 5MP LCD with Independent Sub pixel Drive technology. The depiction detail was greatly improved on MS-S500 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 MS-S500 that employ the same LCD panels of 5MP. As shown in the graph, the MTF of MS-S500 was improved obviously by the Independent Sub pixel Drive function.

 

Furthermore, comparative evaluations performed by radiologists substantiated the clinical benefits of MS-S500 over the conventional 5MP LCD.

 

Fig.2 Mechanism of Independent Sub pixel Drive and comparison of the images of three fine lines


While image quality of the medical monitors 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 Independent Sub pixel Drive, which actualizes excellent depiction ability inexpensively, would be very important in softcopy diagnostic environment.


Q1 Does JVC's Independent Sub-drive technology (ISD), alter the aspect ratio of images as it visually enhances horizontal resolution?

 

A1 No. JVC's sub-pixel technology is driven by activating additional horizontal sub-pixels, thereby increasing the density of the image (three-fold), while the aspect ratio of the native image remains the same.

Q2 The resolution is enhanced three times in the subpixel chain direction of the LCD. What about the resolution in the other direction?

A2 The resolution in the other direction does not change. However, the overall image is displayed properly through special processing.

Q3 Does the ISD technology affect luminance of the LCD?

A3 As the ISD display employs the existing LCD panel used in conventional LCDs, the overall luminance or contrast is basically the same as conventional LCDs. However, because the sampling density from the original image has changed, the luminance at the micro level is changed.

Q4 Is the ISD mode enabled by the ISD display or viewing software?

A4 Both. To display an image in ISD mode, the ISD display and customized viewer software are required.

Q5 Does the ISD technology enable the three-times resolution enhancement by utilizing any LCD panel?

A5 If it is a monochrome LCD with a regular pixel structure that one pixel consists of three sub-pixels, the three-times resolution enhancement is technically possible with the ISD technology.

Q6 Is a special computer or graphics card required?

A6 No. However, we recommend using a computer equipped with a high-speed processor because the amount of data is increased ninefold to use the ISD technology.

Q7 Is ISD technology able to display 256-step (8-bit) grayscales?

A7 The most current version of the ISD technology makes it possible to display 1276-step simultaneously grayscale.