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FrozenGate by Avery
What IC do Laser Range Finders Use?
- Thread starter lbc
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- Jul 4, 2008
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It depends lbc-you really need to use a microcontroller. There are a few popular ways I know of-
1:time-of-flight. It sends a laser pulse out and measures the time it takes to return. Problem:You need about a 500mhz timer to get any kind of accuracy (this will get you about a foot of accuracy).
2:trigonometry. You use a camera type circuit (note-they usually have specialized ccd "strips" for things like this) that measures an angle to the brightest light source it detects. It can use this info to triangulate the distance to the laser dot. Problem:it gets exponentially less accurate the farther out you go.
3:interferometry. I have no idea how this one works.
Anyway, if I were you I would go with option 2. You can use the camera from a wiimote and it will do almost all the work for you, provided you use an IR laser.
1:time-of-flight. It sends a laser pulse out and measures the time it takes to return. Problem:You need about a 500mhz timer to get any kind of accuracy (this will get you about a foot of accuracy).
2:trigonometry. You use a camera type circuit (note-they usually have specialized ccd "strips" for things like this) that measures an angle to the brightest light source it detects. It can use this info to triangulate the distance to the laser dot. Problem:it gets exponentially less accurate the farther out you go.
3:interferometry. I have no idea how this one works.
Anyway, if I were you I would go with option 2. You can use the camera from a wiimote and it will do almost all the work for you, provided you use an IR laser.
HaloBlu
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The wiimote can also see most bright light sources if you remove the IR filter. If you don't have an IR laser at the moment you could likely use another wavelength for testing.
Do let us know if you design anything laser based.
Or non-laser based even.
Do let us know if you design anything laser based.
Or non-laser based even.
Last edited:
ossumguywill and HaloBlu -
Thanks for the suggestion on the wiimote camera. I will check it out. One of the problems I have been having is that the reflection of the beam from the low power pointer is widely dispersed and not really very bright. I definitely need something that is sensitive to weak light signals. I will let you know once I have played with the wiimote.
LBC
Thanks for the suggestion on the wiimote camera. I will check it out. One of the problems I have been having is that the reflection of the beam from the low power pointer is widely dispersed and not really very bright. I definitely need something that is sensitive to weak light signals. I will let you know once I have played with the wiimote.
LBC
HaloBlu
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In case you haven't run across it O-like sells 980nm Infrared laser torch 150mW [OL980-150] - $65.99. Would have to inquire about divergence since its not listed. They told me it has adjustable focus even though its not listed. Might as well ask again to it confirm.
Any shiny surfaces / objects would cause dangerous reflections even with their 65mW one. If fact laser IR reflections should be dangerous at 5mW & even below since you wouldn't blink or look away. You might know that already but its certainly worth mentioning.
780nm or 808nm is not completely invisible, they would look dim red.
Any shiny surfaces / objects would cause dangerous reflections even with their 65mW one. If fact laser IR reflections should be dangerous at 5mW & even below since you wouldn't blink or look away. You might know that already but its certainly worth mentioning.
780nm or 808nm is not completely invisible, they would look dim red.
Thanks, HaloBlu
I think the high power would be too risky for my use. These will be used in projects and experiments for Technical High School students. I would prefer to stay with less than 5mW.
I have found some interesting sensors and technology from Pepperl + Fuchs in Germany and IMF but their components run around $300. Way to pricey to get a bunch for high school students to play with. I may try some optical sensors that generate pulses to drive LED's and contain signal processors.
LBC
LBC
I think the high power would be too risky for my use. These will be used in projects and experiments for Technical High School students. I would prefer to stay with less than 5mW.
I have found some interesting sensors and technology from Pepperl + Fuchs in Germany and IMF but their components run around $300. Way to pricey to get a bunch for high school students to play with. I may try some optical sensors that generate pulses to drive LED's and contain signal processors.
LBC
LBC
