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location Vancouver, Canada
age 45
visits member for 4 years, 5 months
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VP Research&Development at an image guided surgery startup.

Mostly do C++,python,image processing,machine vision - anything with lots of 3D,maths and data. Background is experimental physics and optics.


Aug
30
comment What invisible flicker do different types of light bulbs have?
@jameslarge - you can turn them on and off very quickly. Because of their small size and high efficency the amount of energy in the diode is small and so you can change it's state much more quickly than eg. a filamanet bulb
Aug
29
answered Does a switched on power socket consume electricity?
Aug
29
comment Using a laser to overhear a room conversation
Split the beam, send half to the window and interfere the reflected part with the reference arm. Count fringes and 1 fringe = 1/2 wavelength change in distance to window. Or modulate the laser and track the phase difference of the transmitted/returned signal like a "disto" laser measuring tape. I thought in your original answer you meant you would measure the color change of the returned signal to detect a few cm/s shift imposed on the speed of light and integrate the velocity of the window to get position. I'm not sure it is simple to get a laser with that much wavelength stability.
Aug
28
comment Using a laser to overhear a room conversation
Would you need to measure the speed of the window or merely the position wrt to time. I'm not sure I would use doppler as much as simply an interferometer (ie a phase distance measurement)
Aug
28
awarded  visible-light
Aug
14
revised Can a GPS system detect the decline in the rotational velocity of the Earth?
added 107 characters in body
Aug
12
answered Colour changing material/ink
Aug
11
answered Can a GPS system detect the decline in the rotational velocity of the Earth?
Aug
9
answered thin film interference of light
Aug
9
awarded  thermodynamics
Aug
8
answered Is heat conduction impeded at interfaces between dissimilar materials?
Aug
8
comment If planet orbits are in the shape of an ellipse and the sun is a focus, where and what is the focus?
IIRC the mass of Jupiter means the Sun-Jupiter barycenter is just above the surface of the sun
Jul
26
comment Can we extract positrons from gamma rays?
yes, the problem is more likely to be getting a strong enough source of gamma rays
Jul
25
comment How power lines use high voltages with a low current?
@RJSmith92 the V in the question is the voltage difference along the cable = "wasted" voltage. By having a high voltage/low current cable then with a given R you have a low V difference = low wasted power.
Jul
19
comment Do all stars Turn into Black Holes?
physics.stackexchange.com/questions/99375/…
Jul
18
answered Image formation or Diffraction?
Jul
18
comment How easily can the Earth flip?
@punkerplunk the rotation kinetic energy of the Earth is around 10^29J that's a lot of energy - leaving aside the lack of a mechanism for transferring it.
Jun
21
answered Having trouble understanding spectral lines
Jun
19
awarded  Good Answer
Jun
9
answered Do transformers lose energy?