You don't need a full processor for time of flight just a few transistors which can cheaply operate at ~10GHz. Speed of light / 10ghz = 3cm, but your talking round trip timings so ~1.5 cm is possible.
Multiple frequency phase-shift or Interferometry allows you to do even better.
If they're not going for that kind of precision and range they could simply use ultrasound instead of a laser.
Range on this thing is impressive and precision is too: accurate up to 0.075 ", though they don't specify at what range that precision is still attainable. Typically with increased range on cheap devices you'll get an increase in absolute error so a percentage of the absolute distance would be expected. Maybe that's due to this being a laser device.
Interesting application of tech, a bluetooth enabled range finder could really be useful, especially for realtors that have to measure up a whole bunch of houses on a typical day and that need to keep track of what they measured.
Even more useful if the app would record audio along with the measurements made for later transcription.
Very good point -- you'd have these fast, expensive transistors (however they are packaged or not packaged) cache their data, then transfer it back to a slower, cheaper, main microprocessor, which would be doing the rest of the device's work.
Do you know where these 10 GHz transistors can be found?
Laser rangefinders don't switch the light source at 10GHz. They "chop" the laser on-off at (say) 10kHz. The measure the difference between the reference (onboard) and the return using (typically) a PLL that can measure time differences down to picoseconds (these are usually used in high-frequency RF equipment). Using a microcontroller counter would be too slow.
Multiple frequency phase-shift or Interferometry allows you to do even better.