Goldstone Scientific Blog

Bilateral and Unilateral Fiberoptics for Head-Fixed and Non-Moving Animals

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The Prizmatix Optogenetics LED systems shown on our webstore are configured for moving animals. Many researchers use head-fixed, anesthetized, or other nonmoving animals and wonder what the set up should look like.

How to configure Bilateral fiberoptics without a rotary joint

Many customers want to deliver light bilaterally and wonder if they can connect the Y shaped fiber directly to the Optogenetics-LED and skip the rotary joint.

The answer is “No”, this may not be done.

Why? The connector of the Y shaped fiber has a lot of epoxy filling up the dead space around the two fibers. If the fiber would be attached directly to the LED, the epoxy would melt and damage the fiberoptic and the LED. It is necessary to have a wide core mediating fiber between the LED and the Y shaped bundle. The wide core fiber delivers the light to the two branches.

But not to worry. You don’t need to buy a rotary joint. A FC-FCstationary mating connector can be used instead of the rotary joint. This will reduce the cost of the fiber assembly significantly.

The parts needed are:

Note: When using the FC-LED series which has lower power than our Optogenetics-LED, the Y shaped fiber can be connected directly to the LED without a mediating fiber. In that case, Prizmatix can make a custom fiberoptic with an SMA connector.

How to configure Unilateral fiberoptics without a rotary joint

When the animal won’t be moving and the stimulation is needed in only one implanted fiber, the fiber optics can go directly from the LED to the animal. But the usual “RJ to animal” fiber can not be used. Those fibers have an FC connector, and the LED has an SMA connector. So, the fiber needs a SMA connector on the LED side and a 1.25 or 2.5mm ferrule on the animal side. This special fiber available on the webstore here.

Please contact us if you have any question about how to configure your fiber optics.

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