High-Speed Laser Illumination
Maximize the performance of your high-speed camera systems with short-pulse laser illumination to eliminate the motion blur of fast-moving objects. Tech Imaging Services is the proud US distributor of the versatile and powerful Cavitar CAVILUX HF and CAVILUX Smart illumination lasers.
Cavitar CAVILUX laser illumination products are powerful high-frequency pulsed diode laser light sources designed for high-speed imaging applications. Due to its ability to see through heat and blinding brightness it is especially suitable for studying high-temperature processes and processes that involve small and/or fast subjects. The possible applications include welding, coating, flow and particle measurement, material testing, ballistics, explosions, shock waves and special visualization techniques such as Schlieren imaging.
Main differences between CAVILUX Smart Illumination Laser and CAVILUX HF Illumination Laser
* with peak power reaching the specified pulse power
If visible light is necessary, then Cavitar CAVILUX Smart 640 nm laser is the only matching standard product (not taking into account possible customized solutions). Visible light may be required e.g. due to the properties of the object or camera or due to safety issues. CAVILUX HF laser is equipped with a visible laser pointer beam (green light). Color cameras typically have an IR cut filter in front of the sensor which blocks 810 nm. Some cameras allow the removal of that filter and in this case CAVILUX 640 nm and 810 nm lasers can be used.
Fiber core diameter
Cavitar CAVILUX Smart laser has a fiber core diameter of either 5 mm (400 W @ 640 nm) or 3 mm (500 W @ 810 nm, 200 W @ 640 nm), whereas CAVILUX HF laser has a fiber core diameter of 1.5 mm. This means that CAVILUX HF has 4-11 times higher brightness than CAVILUX Smart. Higher brightness enables the illumination of a smaller area from a certain distance or, alternatively, the illumination of a certain area from a greater distance. Detailed tables about this can be found from the operating manuals of CAVILUX Smart and CAVILUX HF. CAVILUX Smart 200 W provides a higher brightness than CAVILUX Smart 400 W if the illuminated area is smaller than 3 mm.
Minimum pulse duration
The minimum pulse duration for CAVILUX Smart laser enabling full output power is ~20ns. CAVILUX Smart laser can create pulse durations up to 10μs but then the output power is lower. The minimum pulse duration for CAVILUX HF laser at full power is ~50ns and 10μs at lower output power. A very short pulse may be needed for removing motion blur when a small and fast-moving object is studied at high magnification. CAVILUX Smart laser has shorter rise and fall times than CAVILUX HF laser. Therefore Smart can generate extremely short pulses (below 100 ns) more accurately than CAVILUX HF laser.
Max. duty cycle
Due to the difference in duty cycles CAVILUX Smart laser is typically used together with machine vision cameras and CAVILUX HF laser with high speed cameras. CAVILUX Smart laser may also be compatible with certain medium/high speed cameras, depending on the application and camera.
As an example, if the object doesn’t emit thermal light and 100 ns pulses are sufficient for illuminating the object, CAVILUX Smart laser can provide optimal results up to 10 kHz, independent of the minimum exposure time of the camera.
However, if the object emits thermal light (e.g. arc welding), it is usually important that the laser pulse is of similar duration than the camera exposure time (and that the camera exposure time is properly synchronized with the laser pulse). In such a situation, having a camera of 1 µs minimum exposure time, CAVILUX Smart laser can provide optimal results up to 1 kHz (provided that the synchronization between the camera and the laser can be realized properly). Most likely acceptable results can be achieved also at somewhat higher frame rates (up to a few kHz), but the whole camera exposure time won’t be covered by laser illumination anymore (thus making the effects of thermal light stronger than in an ideal situation).
CAVILUX HF is ideal for processes that emit thermal radiation such as welding and explosions and require frame rates about 20,000 fps. CAVILUX HF is also efficient for ballistic applications.
CAVILUX Smart is ideal for flows and Schlieren imaging were very high frame rates and very short pulse durations are required. Example applications are shock waves in combustion and aerospace and drops such as ink jet and sprays. CAVILUX Smart can be also used for welding and explosion applications when frame rates of 1,000 fps are sufficient.
Some examples of high-speed video cameras with short-pulse diode lasers include:
- High voltage switching circuits
- Flow visualization
- Impact visualization
- Shock wave analysis
- Spray visualization