Static image content is typical for specific display applications, such as in the public sector at airports and train stations (traveling information), touch screens (app symbols), or even video gaming in consumer or smartphone displays. A ghost image of the previously static content may remain temporally or permanently visible if the image is updated. This phenomenon is called image sticking, residual image, latent image, image retention, or burn-in.

All LMKs and standard lenses can (usually) be used to measure an image sticking measurement series. Such a series consists of a warm-up, a burn-in and a relaxation phase with different test patterns. One very important aspect is the correct timing between the luminance measurement and the start of the relaxation phase (the change of the test pattern). The patent-protected image-content based trigger for image sticking measurements of our LMK6 models, easily ensures that you always measure at the right time. It thus eliminates the need of complex trigger-setups or input lag measurements. The content-based trigger can be adapted easily to different DUTs, grey levels or customized burn-in and relaxation patterns.

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Three-level burn-in pattern for color sticking image measurement with our image-content trigger setup

In addition our LMK Sticking image add-on can be used to analyze the display burn-in behavior according to two different evaluation procedures. The Three-level and the Two-level approach each have a unique set of display size dependent test patterns and evaluation concepts:

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Burn-in pattern and relaxation images of a three-level measurement series

  • Three-level approach by Dr. Lauer
  • Can be extended to color sticking image
  • Method adapted by the German Flat Panel Forum (DFF)
  • Local or temporal non-uniformity correction possible
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Burn-in pattern and relaxation images of a two-level measurement series

  • Two-level approach by Dr. Bauer
  • Including automatic pattern rolling for warm-up
  • Classical checkerboard burn-in pattern
  • High precision temporal-based non-uniformity correction

In addition, our software offers alternative patterns as grey wedges. These patterns can be used to test for the worst grey level combination of the burn-in and relaxation phase in an efficient and effective way. This was also adapted as a suggested experiment in the DFF image sticking specification.

If you want to learn more about practical aspects of a sticking image measurement, please have a look at our webinar or our related application note. For more details on the theory, please have a look at the references.

LMK BlackMURA

LMK BlackMURA

Add-on for low-frequency uniformity measurements
LMK Display Resolution

LMK Display Resolution

Add-on package for resolution capability (sharpness) measurements
LMK Display Sparkle

LMK Display Sparkle

Add-on for high-frequency uniformity measurements
LMK Conoscope

LMK Conoscope

Add-on for viewing angle luminance and contrast measurements

Downloads

LMK Display (AR/VR/MR) brochure

Publications

SID Vehicle Displays & Interfaces 2019

Modern automotive displays may be sensitive to static content, which remains as an undesired effect of either temporary vanishing or being a static ghost image within the refreshed content. Therefore, there is a development of measurement procedures to quantize the degree of image sticking [1- 6]. Different aspects of these methods as the grey level dependencies or the importance of a temp-oral alignment were considered in [7]. But the mathematically necessary separation of unavoidable initial non-uniformities and the actual image sticking was excluded in that research.
This contribution concentrates on the performance of two selected image sticking evaluation methods [5, 6] from the automotive community and [1] for reference. After briefly introducing the three methods, this contribution focusses on their capability of separating initial non-uniformities from the actual sticking image effect of the target display. Therefore, a mathematical analysis, which is based on a simple but physically motivated sticking image model, is performed. Based on that, an additional non-uniformity correction is proposed. This additional correction has a positive influence on the precision but a negative influence on the measurement time of the fastest measurement method [6]. Thus, we propose a workflow, that decides based on the properties of the DUT whether the correction is necessary or not. All conclusions are supported by simulations and validated using measurement results of a randomly chosen non-uniform automotive LC display.
The aim of this paper is on the one hand to quantize the mathematical influence of the methods and on the other hands to suggest a workflow, which utilizes an existing method and optimizes its application with respect to precision and overall measurement time.
Authors: I. Rotscholl; U. Krüger

Society for Information Display

Image Sticking is an undesired display property, which requires time-consuming and expensive testing. This study summarizes some proposed Image Sticking evaluation methods and identifies relevant differences. It derives aspects, which should be considered prior to a time-consuming and potentially irreversible Sticking Image measurement. Further, parameter analysis associated with the Imaging Luminance Measurement Device is briefly outlined.
Authors: I. Rotscholl; U. Krüger
Aspects of Image Sticking Evaluations Using Imaging Luminance Measurement Devices
Type:
Add-On
Applications:
Automotive Aviation Display
Measurands:
Light measurement
Tasks:
Development & Industry