MicrobeHunter.com Microscopy Forum

Hi guys
Very much a ‘101 in Fluorescence microscopy’ .
3d printed this little holder which will have 3 bright blue led`s (only 1 at the moment) .
The plan was to use a blue light to excite a slide containing some cotton wool with a couple of strands which were stroked with a pink highlighter pen to hopefully show the strands fluorescing (is that actually a word?) when viewed through a yellow filter to bring out the pink strand.
No filter, you can barely make out the pink highlighted strand.


With yellow filter, much better. Its actually a printed yellow filter which ideally should filter out the blue light which it doesn`t really do so a proper one needed.

I think the concentration of blue light also needs to be increased which will hopefully be achieved when I fit the other two led`s.

best

Steve

You might be better off sticking with a single LED and using a lens to focus excitation light on the sample. Light from multiple LEDs is difficult to combine into one bright illuminating spot. We used an LED flashlight with an extra lens. https://calcofi.org/downloads/Posters20 ... agshaw.pdf, https://www.youtube.com/watch?v=w1tG2wj_TAU and https://www.youtube.com/watch?v=BYvU9sOAuFM&t=28s

Yes thanks for that I did wonder about a focus lens. I was careful in designing the holder so all three leds should point to the same spot , will see how that works out
Steve

A long-pass interference filter will remove most of the blue background.

this is really pretty good for a first but I think you should try a filter of a bit deeper yellow to get rid of most of blue light and enhance the fluorescence.

Try with some moss or pond alguae as they fluoresce in bright red

Thanks for that Chris, I’ll give that a try!.
Steve

Otra opción sería colocando un filtro BG -12 (azul verde) frente a la luz (no se requiere filtro amarillo). Por supuesto, los filtros cuestan más que su configuración, pero se pueden usar con cualquier luz de flash brillante para ver la fluorescencia con un estereoscopio y no se necesita un filtro amarillo. Otras luces ultravioletas también funcionan y se utilizan para ver líquenes, rocas, etc.

https://es.aliexpress.com/item/32889032226.html

https://canadiannaturephotographer.com/ ... scopy.html

y no se necesita un filtro amarillo

=

and no yellow filter is needed

You would still need a yellow filter in the emission path as the reflected/scattered light from the BG12 filter would be much more intense than the fluorescence emission from most samples. If a cheap yellow filter is insufficient to block, try a cheap orange filter - or obtain a better quality yellow filter (i.e. sharper cut off and high OD in the blue region).