Laser retro reflector for non-contact odometers.

[Thadwald]

I’m looking for a sensor that will register a bright spot such as tape or white paint on a rotating shaft. I need to accommodate a variety of working distances ranging from 2- 20cm. I’m thinking something like the Waveshare laser module, which has a laser light source and a lensed receiver. I haven’t tried it but I believe I would need a way to tune it for each application, for example by varying the laser power, so that it actually switches. I do like the idea of a visible laser as an aiming aid.

Any suggestions?

 

[Bluejets]

Modulated IR module would do the same job.
Visibility, use your phone camera.
Or phototransistor as used in RC tachos if you have a daylight source.

 

[Delta Prime]

Welcome to Maker Pro
Need to know: mounting system;
ball mount,hard mount etc.
Spectral wavelength in nanometers.
Beam deviation in arc seconds
Exiting Peak to Valley wave front deformation.
These specifications will dictate the type of retro reflector needed
Prismatic or orthogonal.

 

[Bluejets]

Need to know: mounting system;
ball mount,hard mount etc.
Spectral wavelength in nanometers.
Beam deviation in arc seconds
Exiting Peak to Valley wave front deformation.
These specifications will dictate the type of retro reflector needed
Prismatic or orthogonal.

...........really..?????
I think not.

 

[Delta Prime]

Beam deviation in arc seconds
Exiting Peak to Valley wave front deformation

Correction: Exiting Wavefront and Beam Deviation are interrelated please specify one or the other.
I need to know the resolution you seek.

 

[kellys_eye]

Not exactly 2m range but it might be a good enough solution given the cost!

Digital Tachometer with Memory includes Min-Max | Jaycar Electronics

Fast and accurate RPM and surface speed measurements. - 2 to 99,999 RPM - 5-digit backlit LCD - integrated laser pointer

www.jaycar.com.au

 

[Bluejets]

Not exactly 2m range

Requirement was 20cm , or 200mm