Optimal Imaging Sensor Characteristics for Pixel-Level Display Measurement Systems

Posted Sep 09, 2019 by Radiant Vision Systems

Radiant Vision Systems will be hosting a webinar to discuss trends and measurement challenges of high-resolution displays, from OLED and LED displays to the latest microLED panels. It will present the importance of measuring emissive displays to detect common variations at each pixel, and the effect of the measurement system’s imaging sensor on capturing the most accurate and repeatable data from pixel to pixel.

The webinar, titled “CCD or CMOS? - How Imaging Sensor Properties Affect Pixel-Level Measurement of Displays,” will be broadcast live on September 10, 2019, from 10:00 to 10:30 A.M. Pacific Daylight Time (PDT) (1:00 to 1:30 P.M. Eastern Daylight Time (EDT)). The broadcast includes a technical presentation by Radiant Product Manager, Shannon Roberts, followed by a live audience question and answer session.

Imaging systems are highly efficient visual inspection solutions for display measurement and qualification. Images enable contextual analysis of a display to identify defects by comparing visual deviations in luminance, color, and other characteristics across the full display area. The process of converting light to digital input to create an image, however, is not precisely one-to-one—inconsistencies in electronic signals occur as values of light are translated into electronic data. Imaging sensor types (CCD and CMOS) accomplish this conversion process in different ways, each with distinct benefits and limitations.

Inevitable inconsistencies may be more or less apparent depending on the sensor’s properties—hindering or improving imaging system performance. Understanding the effect of imaging system specifications and sensor properties is critical for choosing a system that optimizes the accuracy and repeatability of measurement data. This becomes even more important when evaluating the extremely limited data-sampling area of a single display pixel—a significant quality indicator for todays high-resolution, emissive displays, such as OLEDs and MicroLEDs (µLED).

With over 25 years manufacturing imaging systems for display metrology, Radiant’s engineering efforts have continued to evolve with market trends to address the smaller size of display pixels, increasingly dynamic integrations, and the need to ensure data accuracy within more precise light-emitting elements. Radiant’s ProMetric Imaging Photometers and Colorimeters are designed to achieve high resolution while maintaining signal-to-noise advantages necessary for repeatable measurement data across thousands to millions of display pixels.

Radiant works directly with image sensor vendors to evaluate imaging performance for each system and accepts only scientific-grade components that achieve resolution benefits without sacrificing image quality and measurement capability. Within a single measurement image, a ProMetric imaging system can capture highly accurate luminance data at each pixel in the display, enabling comprehensive and efficient visual inspection (under 1.5 seconds per measurement) in both lab and production applications. 

At Radiant’s upcoming webinar, Product Manager Shannon Roberts will present the impact of imaging system specifications on measurement performance in display metrology. The presentation will include measurement examples that compare sensor type (CCD versus CMOS), pixel size, and signal-to-noise ratio (SNR), and the effect of these properties on the accuracy and repeatability of data for pixel-level display measurement.

Click here to register for the webinar.