Several illumination sources are available for machine vision applications. These include incandescent, fluorescent, halogen, and LED lights. The selection of the right source depends on several factors, including the specific application, the spectral properties of the light, and the geometry of the light source.
Incandescent lights
Incandescent lights produce light by heating a wire filament enclosed within a glass bulb. When operating, most of the energy generates heat resulting in poor energy efficiency. They also have a short lifespan. On the plus side, they are inexpensive to purchase and have a continuous spectrum.
Fluorescent lights
Fluorescent lights are available in various shapes and designs. They produce diffuse light and minimal glare. However, they degrade over time, are not dimmable, and have a discrete spectrum, typically with spikes in blue light. They are generally inexpensive to purchase and maintain.
Halogen lights
Halogen lights are very intense and last longer than fluorescent lights. They are better for bright lighting applications at the expense of being extremely hot. These lights have a continuous spectrum, including near ultraviolet, visible light, and infrared. However, they are more prone to flicker, lose intensity over time, and have poor strobing capabilities.
LED lights
LED lights shed the above weaknesses while retaining the strengths. For this reason, they have become the go-to choice for machine vision applications. LED lights are:
- Small and light
- Cool when operated
- Relatively inexpensive
- Extremely energy-efficient
- Less sensitive to vibration and motion
- Able to be used with diffusers and lenses
- Capable of being used outdoors and in cold weather
- Available in broad-spectrum, specific colors, and/or infrared wavelengths
- Capable of pulsing light synchronized with the camera image to create a brighter scene and to “freeze” motion
- Long-lived, lasting up to 100,000 hours (over ten years)
- Temporally and spatially stable
Wide range of LED pricing
Well-known brands like CCS create excellent LED light solutions for machine vision applications and industrial inspection. However, their lights come at a premium price. Light186 offers similar lights priced 50% to 300% lower.
Light186 lights are very high quality, as witnessed by customer Mark Strangio-McRae, Founder of Vision AI in Australia.
“We are all impressed with the unit’s build quality and, more than that, the lighting output. It works as designed, and we are delighted. Light186 will be my first option for lights for future projects.”
In short, LED lights are the best choice for most machine vision projects and can be found at very affordable prices.
