Key Parameters Of Medical Imaging Display--The Brightness
With the development of the IT industry, digital imaging systems (PACS, DR, CR,
With the development of the IT industry, digital imaging systems (PACS, DR, CR, Angiography System(Cath Lab), etc.) are more and more favored by domestic hospitals because of their soft-reading functions and forward-looking.
However, due to cost considerations, in terms of digital imaging systems, the configuration of medical monitors is often ignored or discarded, and ordinary PC monitors or black and white monitors are used instead, which makes the image display effect reduced.
As the "last mile" of the digital medical imaging system, the image quality of the medical display is an important basis for the doctor making the diagnosis. Compared with ordinary displays, medical displays have key indicators such as higher resolution, brightness, and calibration curves that conform to the characteristics of medical image displays, which are key factors to ensure image accuracy.
The ability of the human eye to distinguish gray scales has a nonlinear relationship with the difference in brightness. The higher the luminance, the more JND can be distinguished by the human eyes. Conversely, with low brightness, the human eye to gray scale resolution is poor. In order to improve the resolution of the grayscale, the brightness of the display should be high.
The ambient light in the doctor's reading room has an effect on the brightness of the monitor. The bright part of the display image depends on the brightness of the display, but the dark part is not only related to the brightness of the display, but also related to the brightness of the environment and the refractive index of the display.
The maximum brightness of the medical display is 600-800cd/m². The brightness of ordinary monitors is 200-350cd/m². The American College of Radiology (ACR) stipulates that the maximum brightness of digital X-ray images should be at least 170cd/m².
In March 2001, at the X-ray Imaging Symposium in Germany, the opinion was mentioned that the brightness of the display is at least 200cd/M2. Considering that the brightness of LCD monitors will decay over time, it is recommended that the brightness of new monitors should be at least 500cd/m² or more.
After the highest brightness of the medical display is installed in place, it is corrected according to the DICOM standard by means of optical correction, so that the brightness can be maintained at a brightness value required between 400-500cd/m² for reading the film, and to ensure constant in 3-5 million hours.
From this point of view, the actual functions of ordinary monitors and medical monitors in the working environment of the medical radiology reading room are very different.
