Technology Developments Take CCD Imaging Colorimetry Out of the Lab and Onto the Factory Floor

Posted:  
Mon, March 20, 2017
Author: 
Radiant Vision Systems  | 

CCD Imaging Colorimetry on the Factory FloorManufacturers of flat panel displays, illuminated keyboards, and LED lighting products need accurate, repeatable, and easy-to-use light and color measurement solutions to ensure product quality, generate data, and improve efficiencies on the production line. In today’s marketplace, where margins are thin and customer expectations high, many manufacturers are discovering a competitive advantage in imaging colorimetry systems. Once almost exclusively the realm of R&D labs, these specialized CCD-based systems combine the benefits of automation – speed, flexibility, and repeatability – with the relevancy and accuracy of human vision. Recent innovations in the technology include production-friendly features to meet the speed, accuracy, and connectivity requirements of high-volume manufacturing environments.

Production-Ready: ProMetric IProduction-Ready: ProMetric I

Introduced in 2013, Radiant’s ProMetric I Series Colorimeters exemplify this trend. ProMetric I includes Smart Technology™, designed to significantly simplify measurement setup and enable fast, accurate measurements that match human perception of brightness and color. The addition of a high- resolution, high-speed CCD sensor enhances spatial measurement accuracy and reduces total measurement time by 5-10x when compared with full-frame CCDs. This enables customers to conduct more thorough testing with a reduced cycle time.

New CCD and Electronics Technology Enable High Speed Operation and Production Reliability

Interline-transfer CCDs enable high-speed measurement applications because the image capture and readout processes can occur simultaneously. However, Full-Frame technology has generally been considered the better choice for high accuracy, high precision applications. With recent advancements in electronics, scientific grade interline CCDs can now attain accuracy close to that of R&D grade Full-Frame CCDs. The ProMetric I family comprises three models: ProMetric I2, I8, and I16, built around 2MP, 8MP, and 16MP scientific-grade cooled interline CCD sensors, respectively.

In a Full-Frame CCD, the entire detector surface is first exposed to light and then the light must be externally blocked off so that readout can occur without further charge accumulation. On an interline-transfer CCD, by contrast, alternate columns of the detector array are masked off with an opaque material. To read out the image, the charge in each column of illuminated pixels is shifted, simultaneously, to the adjacent “dark” column that is blocked off from light. New image information can be accumulated in the open “light” pixels while this is occurring. This has the effect of allowing relatively faster exposure times and allows exposure time to be controlled electronically.

 

Interline Transfer Technology Enables High Speed Operation

Connectivity Options Facilitate Integration into Manufacturing Operations

Reliable communications in production line environments is critical. ProMetric I supports both high-speed USB and Ethernet connectivity for highly reliable operation over long distances - even in difficult manufacturing environments.

Turnkey Solutions for Manufacturers

ProMetric I works with the Radiant TrueTest™ Automated Visual Inspection system. TrueTest software serves as the engine for image analysis, to identify defects and quality issues, quantify their magnitude, and assess measurements to make pass/fail determinations. The integrated hardware/software system delivers a complete, turnkey solution for high-volume manufacturing of FPDs, illuminated keyboards, and lighting products.

Summary

ProMetric I imaging colorimeters deliver highly accurate color and luminance measurements in the demanding constraints of automated manufacturing environments. ProMetric I is engineered around a high-resolution CCD sensor that enables pixel-level measurements on FPDs, intra-character luminance measurements on illuminated keyboards, and highly accurate measurements of LED luminance and color in luminaires with large LED arrays. The high-speed operation of ProMetric I allows for significantly more complete test coverage without impacting overall throughput, so users can improve product quality and reduce costs by capturing and quantifying defects before they make it to market in finished products.