Front Lighting

A front lit scene (where the MicronEye is on the same side of the scene as the light source or ambient light) sometimes lacks adequate contrast. Front lighting with a diffused light source can often be used to increase the contrast in a scene. If defects or points of interest are to be emphasized, side lighting such that the defects or points of interest cast a shadow or appear brighter through increased reflectivity may be used.

To set up a front lit scene, one or more flood lamps (found at most hardware stores) are arranged around the scene far enough away so that there are no shadows. Then the f-stop, focus control and lamps are adjusted for maximum contrast and focus. It is usually helpful to adjust the focus where the smallest part of the scene has the most detail.

In many instances you will want to diffuse the light coming from the flood lamps. Diffusing the light increases the uniformity of the light on the image. You can diffuse the light as simply as placing a piece of paper over the lamp. A better method of diffusion is to take a sheet of frosted mylar, diffused white plastic, or a sandblasted pane of glass and place it between the lamp and the subject. A diffused light source is most commonly used in defect detection and visual inspection applications.