Hi, I need some advice.
I'm working on my engineering physics capstone project. We've been asked by our sponsor to build a high-speed camera to take pictures of ultrasonic pulses travelling through water. At the frame rates and resolutions required for this application, there is no high-speed camera available on the open market for any price, so we're going to make a composite video from pictures of thousands of individual pulses.
The trick is that we need/want sub-pixel blur as the wave moves across the image plane. For a 5cmx5cm image plane, with speed of sound in water 1500m/s, and using a 4Megapixel camera, the wave moves 1 pixel about every 15ns. This means that we need to use a Q-switched laser to illuminate the pulse, and that the pulse duration needs to be < 15ns.
I have a few considerations:
- We want to trigger the pulses, or at least time the pulse repetition frequency to be exactly the same as the camera's framerate
- I want to generate enough light to illuminate the CMOS camera chip without saturating or cooking it.
- I have a 15k CAD budget for the whole project, but I can't blow it all on a laser. I need camera, optics, water tanks, laptop computer, etc...
- The response of the camera that I think we'll be using is best in the 450-700nm range, and infared lasers will probably not through the glass lenses that we'll be using.
Can anyone advise me on how to go about getting a controllable (Active) Q-switch laser with pulse duration < 15ns? I've found some stuff on ebay, but I'm hesitant to blow half my budget.
Thanks.