Display calibration and adjustment

Calibration

In no other field is a precise image display as important as in the medical environment, for example in radiology or surgery.
However, in order to ensure a consistent image display, it is not only important to use a high-quality display, but also to calibrate it.
Calibration is the adjustment of two values to a defined value.
Important parameters to be calibrated are brightness, gamma, color temperature and color space.
These must correspond to a defined value and be kept constant.
The brightness is measured at white and is referred to as Lmax.
Integrated ALS (Automatic-Luminance-Stabilization) ensures that brightness settings remain stable.
Another parameter is the display gamma.
This measures the relationship between the input signal and brightness.
Gamma is therefore the brightness correction for the grey values of the monitor, i.e. the levels between black and white.

LUT

A central element of color calibration is the lookup table (LUT).
This serves as a translation table between input and output.
The adjustment at the factory or by the user determines which input value is linked to which output value.
The size of the LUT is decisive for the result.
The more gradations are possible, the more precise the calibration can be.

3D LUT calibration

The perceived color distance is referred to as Delta E and reflects the difference between two values.
This distance can be further minimized with the new 3D LUT, as it offers the possibility of creating a 3 x 3 matrix, whereby R, G and B channels can be controlled independently of each other.

BT.709, BT.1886 and BT.2020

All colors that are actually output are displayed in a three-dimensional color space.
Color space refers to the subset of the color range that is visible to the human eye.
The best-known color spaces are BT.709, BT.1886 and BT.2020.
BT.709 standardizes parameters for HDTV with an aspect ratio of 16:9.
BT.1886 was then defined to standardize the gamma curve for HDTV flat screens.
The extended color space according to BT.2020, which focuses on various aspects of UHDTV, is currently an exception.
This color space exceeds the color space of all currently available panels.

Why Rein Medical?

The Rein Medical UHD high brightness monitors have: – ALS (Automatic Luminace Stabilization) which keeps the monitor at a stable brightness value over its entire service life.
– Innovative 3D LUT calibration for DICOM, BT.709, BT.1886 and BT.2020 for perfect display of grayscale and colors – Factory calibration of each device before delivery.