Virtual reality (VR), augmented reality (AR), and mixed reality (MR) devices rely on the quality of near-eye displays (NEDs) to deliver a seamless immersive or integrated experience. AR/VR/MR displays project visual objects and information in close proximity to the human eye—encompassing the user’s entire angular field of view—so that visual details created by variations in the brightness and color of the display are magnified to create simulated and augmented worlds. However, this proximity also magnifies what would be unnoticeable display defects if seen at a distance.
Subtle defects and anomalies can include:
- Non-uniformities in brightness or color
- Contrast issues
- Mura (cloudiness)
- Line & pixel defects
- Focus uniformity issues
- Distortion or ghosting
- Image retention/sticking (or pixel switching response time)
Display defects have a critical impact on your users’ experience, potentially obstructing visualization and device operability. Additional considerations include image distortion and inconsistencies from eye to eye (color, angle, parallax), which can further impact user experience and result in eye strain or even motion sickness.
It requires sophisticated inspection capabilities to achieve the product quality customers demand. Radiant Vision Systems is a pioneer in display testing for AR/VR technology, offering the highest spatial resolution in light and color measurement for detecting, classifying, and preventing subtle light uniformity issues and pixel and sub-pixel defects. Radiant has developed inspection solutions that replicate the human eye’s visual response in a wide range of:
- Visual experiences (immersive or see-through)
- Display types (LCD, OLED, microLED, LCoS, or DLP)
- Viewing channels (monocular, binocular, or bi-ocular)
- Optical design (opaque display, free space, freeform, lightguide / waveguide, metasurface, holographic, curved mirror, birdbath, or custom optics)
Measuring Augmented Projections
Projections of AR and MR displays are superimposed over a user’s visible surroundings to supplement the real world with digital information. As with head-up displays (HUDs) used in the latest automotive and aerospace technologies, these projections must seamlessly blend and interact with physical elements in view at a variety of locations and depths. To function correctly, AR and MR projections require precise control of position, light, and color for viewing on an infinite plane.
AR and MR displays are extremely susceptible to errors in visual depth when projections are not mapped correctly for parallax (accounting for the horizontal distance from eye to eye). Devices must be able to match the size, shape, and position of projected images as viewed in each lens—or in each display in the case of binocular devices. Object position, brightness, color, and contrast are critical benchmarks of depth and location relative to surroundings. As a designer or manufacturer, you must be able to control each factor to ensure that projected content is bright enough to be seen, but also does not obstruct the user’s view of the real world.
The Power of ProMetric for Precise AR Measurement
ProMetric imagers have helped to define the baseline SAE (Society of Automotive Engineers) testing parameters for HUDs in the automotive and aerospace industry, where the accuracy of projected data is a critical safety factor. Radiant’s expertise in precision visual display measurement is also applied to AR and MR displays. Our imagers can measure objects projected into infinity, using highly-sensitive scientific-grade image sensors to locate superimposed objects projected into an ambient environment. ProMetric cameras feature:
- Electronically controlled lenses that allow you to remotely adjust camera focus and aperture settings. These cameras are uniquely capable of locating augmented projections
- Advanced software algorithms that use focal settings to measure size and position to determine object “distance” in real-world measurements without the need for focal depth calculation
- Light and color accuracy measurements to determine accurate brightness (highlights or shadows) in respect to the environment, contributing to the projection’s visibility
- Evaluation against defined tolerances for luminance, color, and spatial offset. You can accurately determine an artificial object’s location, depth, and size
- Library of tests and patterns such as checkerboard patterns to measure slant edge contrast or modulation transfer function (MTF) to ensure object clarity
Wide-field-of-view images taken by a camera/lens solution before and after distortion calibration. Distortion calibration of each system eliminates lens effects in wide-field-of-view images to ensure accurate spatial data is acquired by the software before testing.
Complete Project Support Worldwide
With a global network of sales, technical support, and engineering resources located across the United States, Europe, China, Japan, and Korea, our local professionals are here to see your project through from start to finish. Radiant’s portfolio includes configurable software, modular imaging systems, and accessories, giving you a single solutions provider to address all aspects of your test and measurement application. Whether you need a system for R&D, quality control, or production – or systems throughout the complete device manufacturing cycle – our staff partners with you to specify and implement your unique solution, and offers technical support long after your system is deployed.