CS-ECTS-TC04 Slanted-Edge Test Chart for Endoscope Image Performance Testing — Sharpness, SFR/MTF and Depth-of-Field Evaluation

ColorSpace has developed the CS-ECTS-TC series of endoscope test chart for medical and industrial endoscope imaging systems. The CS-ECTS-TC04 Slanted-Edge Test Chart features a Slanted-Edge test target for evaluating image sharpness, edge response, and spatial frequency response (SFR/MTF) of endoscope imaging systems. By capturing the same slanted-edge target at different working distances, the chart can also be used to support evaluation of the range over which the system maintains clear imaging (depth of field).

The test chart uses a Slanted-Edge test pattern. Analysis of the imaged edge can provide the Edge Spread Function (ESF), Line Spread Function (LSF), and Spatial Frequency Response (SFR). Depending on the applicable measurement method, the results can be further used for MTF analysis. These measurements provide objective data for evaluating image sharpness, edge response, and spatial frequency performance of endoscope camera systems.

For depth-of-field evaluation, the same slanted-edge target can be captured at different working distances. Changes in image sharpness or SFR/MTF performance across different distances can then be compared to support evaluation of the range of distances over which clear imaging is maintained. In this application, TC04 serves as a standardized test target for depth-of-field evaluation rather than a standalone depth-of-field measurement method.

For FDA-related applications, image resolution and other imaging performance characteristics may form part of the performance evaluation for applicable endoscope devices submitted through the FDA 510(k) pathway. Depending on the device and test protocol, resolution may be evaluated using methods such as USAF resolution targets or MTF-based measurements. SFR/MTF data obtained with TC04 can, where applicable, serve as part of the supporting image-performance evidence for such evaluations. Specific test methods and acceptance criteria should be determined according to the device, submission pathway, and applicable regulatory requirements.

ISO 12233 specifies methods for measuring resolution and spatial frequency response in digital cameras and general digital imaging systems and can serve as a general technical reference for slanted-edge SFR/MTF measurements. ISO 12233 is not an FDA-designated test method for medical endoscopes. For medical endoscope optical performance evaluation, applicable requirements and test methods should also be considered in conjunction with the ISO 8600 series and the relevant product-specific standards or test protocols.

The chart features a glass transmissive design and can be directly mounted on the CS-ECTS Endoscope Test System, providing a standardized setup for endoscope image performance testing.

Chart Specifications Parameters：