Machine Vision Lighting By Sam Mitchell 10/5/2012

Lighting Components

Lighting Components Linear Lights Spot Lights Ring Lights Used to light a rectangle or along a path There are also curved linear lights Spot Lights Used to illuminate specific areas Adjustable distances and spot sizes Ring Lights Goes “around” camera Can mount to lenese Light to Camera Connectors Connects the light to the camera. Used to only activate the necessary lights so the rest of the area can be dark Color filters Changes the light to the ideal color to improve analysis

Limitations/Pitfalls Color When using a color light, the color on the opposite side of the wheel appears very dark Contrast There needs to be a big enough contrast between the environment and part.

Color

Use Specular reflection Light reflected off target directly back to camera. Effective for inspecting highly reflective targets (i.e. glass) Diffuse reflection Light dispersed in many directions off surface of target. Effective for inspecting targets through reflective packaging. Transmitted light Light applied from behind target, camera sees target silhouette. Effective for dimensional measurements.

Class Problem If you were to use machine vision to recognize the defects on oranges what kind of light would you use?

Class Problem If you were to use machine vision to recognize the defects on oranges what kind of light would you use? Diffuse orange colored

Industry Standard The connectors from camera to control seem to be an industry standard Industry standard for mounting

Videos http://www.youtube.com/watch?v=7lGjMw2hUBs http://www.youtube.com/watch?v=Rq0or5Ev0QA

Summary Lighting is used to setup the scene so that the image comes out clear and can be processed correctly. Watch out for color, ambient light and reflections

References Paper http://www.smartvisionlights.com/ http://www.theimagingsource.com/en_US/ http://www.ni.com/white-paper/6901/en