Structure: The uniformity of direct illumination is not very good, but dome light and some other shadowless diffused light can get quite good uniformity, like dome light, it used hemisphere structure, and reflect the bottom ring light by the hemisphere structure to the object, the uniformity and lighting direction is excellent, and can get quite uniform area in a certain circle. This way can make the different shapes light to get uniform light. Vault light has the similar principle, it makes bar light to get uniformity by the reflection.
Application: Used for the configure inspection, location, and size measurement of the reflective and uneven surface.
Advantages: whole uniformity is good, and image result is stable.
Disadvantages: inverted image caused easily on the glass surface.
LED machine vision lighting: dome light, vault light, low angle square light, low angle ring light, big back light as front light, box light and so on.
|Original picture||Image result of ring light||Image result of dome light|
Razor bracket inspection image result comparation of ring light and dome light
|Stitch needle inspection||IC pin location|
|Printed code inspection||Die bonding line inspection||Letters inspection of keypad|