Which instrument uses a black or gray matte-finished cloth as its testing surface?

• A. Harrington Flocks Screener
• B. Amsler Grid
• C. Automated Perimeter
• D. Tangent Screen

Answer: (D)

The key idea is the testing surface used for manual visual field testing. A tangent screen is specifically designed with a black or gray matte-finished cloth stretched over a frame to provide a non-reflective, uniform background. This matte surface minimizes glare and reflections, allowing the tester to project light stimuli at various locations without interference, which is essential for accurately detecting peripheral vision responses.

The other options don’t use this kind of testing surface. An Amsler grid is a near-visual-field chart printed on paper and viewed at a fixed distance; an automated perimeter is a computerized device that presents stimuli on a screen or inside a bowl, not a cloth surface; and a Harrington Flocks Screener is not defined by a matte cloth testing surface in standard perimetry practice.