Coaxial light is designed specifically for “glossy flat surfaces.”
■ Glossy flat surfaces (suitable for coaxial light)
For example, with objects like the ones below, the resulting image would appear as shown on the right.
The caliper also appears as shown on the right.
■ Glossy surfaces with irregularities or curves (not suitable for coaxial light)
Driver
The image will show only the top of the curve (R) illuminated.
Drill bit
The image will show only the edge illuminated.
■ Non-glossy (diffusely reflective) flat surfaces (not suitable for coaxial light)
Paper (printed material)
Using coaxial light results in a dull image. When observing printed material with a “ring light”, the image appears clear, as shown on the right.
