I've made a small hexagonal array of 7 transducers spaced 2Lambda apart (1 in the middle and 6 around) and it narrows the beam width from 70 degrees to about 30 degrees. Curiously there is a dip on the bore-sight.
We have an other thread talk about water level measurement;-The method is discussed at thread:UltrasoundPressure sensorX band Proximity SensorKu band Proximity SensorK band Proximity SensorSound315MHz/433MHz rf-link Arduino (radio waves blocked by water)Bluetooth Proximity SensorVLF radio waves (3-30 kHz) (radio waves through by water)Laser-based water level sensorCapacitance proximity sensorResistance proximity sensorMeasurement the pump discharge pressure (if there is pump)Float switchhttp://arduino.cc/forum/index.php/topic,160378.0.html
Something I'm curious about: Will we ever see any of your code, schematics, or physical setup, sirch?
Yes, I have developed a laser based system (see the CREG Journal a couple of issues ago). The thing with laser systems is they are generally beyond me to integrate into a larger system (can't build a modulated or time-of-flight system and hacking something on to a ready build system is very hard, I've tried).
Plan C;-GM100DU USB Photoelectric Laser Distance Meter price: $100.00 USD qtydistance:100 Maccuracy: +/- 1.5 mmsearch ebay, USB only no TTL UART.
Plan B;-LR4- Interface Board for Fluke 414D Price: $149.00 FLUKE 414D /Newark Price: $129.95Total: $280.00http://www.porcupineelectronics.com/distance:50 Maccuracy: +/- 2.0 mm