Very interested in this. Let me know how i can get my hands on one of these!
OpticsThe optical components have arrived at last!The lenses are 25mm diameter on both the laser and receiver. In the case of the laser, the purpose of the lens is to collimate the outgoing flash of laser light. This is necessary because, unfortunately, the light that comes from a semiconductor laser doesn't have a nice parallel beam. Instead, it comes out in a distorted cone shape that needs to be made parallel in order for the laser light to travel as far as possible without getting spread out and becoming too faint. This collimation process is often done with very fancy optics in order to get the maximum theoretical range. In this design however, a single lens element should be enough to get the laser beyond the 25m range specified for the design. The diameter of the laser beam will be the same as the laser lens (25mm) as you can see from the picture below.The laser beam projected onto a Phosphor cardThe lens in front of the receiver serves a different purpose. It acts as a light gathering area that focuses the rather weak return signals from the target onto the APD detector. The bigger this light gathering area is, the greater the distance that the range finder will be able to measure. This makes it very easy to increase the range - just use a bigger lens. For the purposes of this design, the 625 mm2 of the receiver lens should give us the desired range.Optics - front viewFrom the picture above you can see that the optical arrangement is very sturdy. This is necessary to ensure that the alignment of the lenses stays absolutely fixed. If this alignment changes then the laser will end up pointing in one direction whilst the receiver points in another - and that means no return signal!To get the laser and the receiver lined up correctly in the first place there is an alignment and focus mechanism for both the laser and the receiver circuit boards (see below). These mechanisms have three degrees of freedom (the ability to be adjusted independently in three orthogonal axes, X, Y and Z). By adjusting the position of the laser and receiver whilst watching the strength of the return signal on an oscilloscope, it is quite easy to achieve almost perfect optical alignment.Optics - rear view
// SPI Hardware#define SPI_CHIPSELECT_PIN 10#define DATA_READYN_PIN 9
I looked up the data sheet for the DS00VQ100 chip and it's only 12.8MHz
I looked at the schematic for my phone - the highest frequency section is probably the 5GHz WiFi, yet the clock for that is derived from a 48MHz crystal.(If it didn't have the 5GHz band option, then the 2.4GHz band would be clocked from the same 19.2MHz crystal that provides the system clock for the 1.7GHz processor)
This is different, that's just a carrier signal.