Backlights

Backlights are used to highlight the edge of a part, openings within a part (dilled or machined holes), or hide transparent materials. Note that backlights do not need to be directly under the object but may actually work better with a space between the product and the light itself.

Watch for: Edge line clarity or blurring on round parts, especially

Bar Lighting

Bar lights offer uniform, linear illumination with flexibility to adjust the angle of the light based on the application. Bar lights are great for creating contrast on matte surfaces such as paper, cardboard, or rough surfaces.

Watch for: Unevenness on round surfaces and hotspots.

Coaxial / On-Axis

Coaxial lights are great for highlighting edges and height changes on a part. Coax lights are good on flat metal surfaces, not ideal for curved surfaces. Coaxial lights are unique in that you can light objects from the same axis as the vision system.

Watch for: Clean definition on raised edges.

Darkfield Ring

Darkfield Ring lights, with LEDS mounted at 90degrees, highlight the edges of a part as well as emphasize the height changes on a surface providing increased contrast. Light must be very close to object (short working distance).

Watch for: Details with embossed or engraved markings at close distances.

Dome

Dome lights provide even, shadowless illumination. This type of lighting is used most often with round surfaces, especially shiny metal curved surfaces. Dome lighting hides surface height changes and creates a flat look.

Watch for: Even, flat image quality and diffusion.

Low Angle Ring

Low angle ring lights offer great contrast on objects with raised edges providing more flexibility with light work distances compared to dark field ring lights. LA ring lights are especially good to use on shiny surfaces.

Watch for: Difference in contrast at close versus far distance levels.

Ring

Standard ring lights cover a very large range of applications and are very versatile in their use. They provide shadow-free illumination as the ring covers entire working area and are a more common lighting type within the machine vision industry.