[Laser] Source of Optical Bandpass filter

[Paul Cianciolo]

Hi Folks,

Does anyone know a source for "relatively" inexpensive band pass filter.

I have some experiments to try, and would need something for 650nm to 690nm?
The filter would be just ahead of the detector and initially I would use red
diode laser.

I have some wratten #29 and 92# that seem to work well.  Maybe for the night
sky IR is not a problem?

Anyone know about this?

W1VLF