# Dichroic mirrors that reflect two wavelengths

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1. May 23, 2015

### gkiverm

In fluorescence microscopy, dichroic mirrors reflect light under a critical wavelength (used to excite the sample) and transmit light over a critical wavelength (emission light from the sample). Are there mirrors that reflect two different wavelengths of light and transmit the rest? Essentially a dichroic mirror with two regions of reflection and two regions of transmittance instead of one each.

2. May 24, 2015

### Ygggdrasil

Yes, these are often referred to as polychroic mirrors, dual-band dichroics, or dual- edge dichroics. If you're using two laser light sources, you could also get away with a standard dichroic to get rid of the shorter wavelength excitation light, and a notch filter to get rid of the longer wavelength excitation light.

3. May 29, 2015

### gkiverm

Are there also filters that only allow two ranges of wavelengths to pass through as opposed to one? Basically a band pass filter with two regions of transmission. I'm sorry, I'm having little luck finding this online for some reason.

4. May 30, 2015