A conoscope enables the characterisation of a display's appearance under different viewing angles. This is crucial not only for multiple viewers but also for a single user, especially with larger displays. The corners of a large TV, for instance, are viewed from a significantly different angle than the center, highlighting the importance of understanding how the display performs across a range of perspectives. While it might be perceived as the reserve of specialist academic research, technological advancements in conoscopic equipment have opened up more commercial use cases for OEMs, with the technique finding its way into new and interesting applications.
What is conoscopic measurement?
The technique involves observing a cone of converging light rays. This can allow simultaneous analysis of light propagation in multiple directions.
When it comes to emerging commercial applications, conoscopic display measurements are particularly suited to quality control in display manufacturing - a growing market that is set to get even larger. According to Fortune Business Insights, the global display market size was valued at $147.61bn in 2023, and the intelligence firm predicted that it will grow from to $295.04bn.
The report cites continued development of display technology as a key driver, leading to innovations including flexible displays, touch integration, and high-definition resolution to improve user interaction and visual experience. Already widely used in consumer electronics, displays are also playing a key role in a number of other industries, including healthcare, automotive, retail, and entertainment.
To take advantage of the opportunities provided in this market, manufacturers and OEMs need to be able to ensure that their displays meet specific optical standards and deliver high-quality visual performance in terms of color accuracy, contrast, and viewing angle consistency.
This is particularly the case when it comes to the viewing angle, or range over which the display can be ideally viewed. Depending on the application, the display may need to be optimally viewed from all directions, and not lose picture quality if, for example, the user needs to move around with the monitor or device, or for passenger displays, to ensure that the driver is not impacted or distracted by the display.
Viewing angles are typically measured from one side of the display to the other, horizontally and vertically. The displays can exhibit varying performance along the horizontal and vertical axes, which means that manufacturers and users need to define the maximum usable viewing angles for each direction.
The challenges of conoscopic measurement for viewing angle measurement
Historically, conoscopic measurement systems, such as those incorporating Fourier lenses, have proven to be accurate when it comes to measuring the viewing angle of displays.
However, these may also often come with prohibitive price tags that can exceed six figures. They can also be bulky and require precise alignment, which has previously limited their use to controlled laboratory environments. In addition, polarisation effects can occur during the measurement of displays, which can add additional complications and change the quality of the picture.
The Admesy solution
Enter Admesy, with its recently developed Admesy Helios Color Conoscope, which was designed to advance display measurement technology, with greater accessibility and versatility in viewing angle and colour characterisation, while also providing a solution for applications such as production, end-of-line quality control.
The Hekios Color Conoscope emerged to help OEMs overcome the aforementioned challenges in order to provide a more accessible solution that is more within reach when it comes to cost. Imagine, for instance, being able to comprehensively analyse a display's performance, from viewing angles to color accuracy, with a lightweight device. That's the promise of the Helios Color Conoscope. The device measures incident angle of 0-50° and azimuth angle of 0-360° with an optical resolution smaller than 5°. This helps allow professionals to capture a wider range of optical measurement characteristics that would previously have required much larger and more expensive instruments.
Precision where it matters
What sets this device apart is its holistic approach to display characterisation. Beyond luminance measurements, the Helios Color Conoscope provides further metrics, such as colour accuracy, gamma characteristics, and contrast ratio. The device was designed to be the first solution available in the mid-price range to achieve all of this, therefore making the technology more widely accessible to those with a smaller budget.
And, when it comes to tackling the issue of polarisation during testing, Admesy has the in-house expertise to provide specially coated filters to minimise the impact of these polarisation effects.
Multi-industry applications
The applications are as diverse as the industries that demand precise optical measurements. From R&D laboratories seeking comprehensive display characterisation to production environments requiring fast, accurate quality control, the Helios Color Conoscope is ideally suited. End-of-line inspections, quality control processes, and advanced research could all benefit from its capabilities.
Find out more about the Admesy Helios Color Conoscope by dowloading the latest White Paper.
