NIGHTSEA™ Vorsatzlinse für LED-Lichtköpfe

The NIGHTSEA™ SFA Focus Lens is an accessory designed to enhance the performance of NIGHTSEA SFA fluorescence illumination systems by focusing the excitation beam onto a smaller area.

Depending on the selected focal distance, the illuminated spot size is significantly reduced, resulting in substantially higher excitation intensity. The 50 mm version provides an excellent balance between brightness and working distance, while the 30 mm lens delivers maximum intensity for applications such as photoactivation or imaging weakly fluorescent specimens.

The lens simply slides onto the existing SFA light head and is securely held in place by friction, allowing quick installation without tools or permanent modifications.

It is available with two options for the focal distance: 30mm or 50mm. 

No lens: illumination spot approximately 15mm diameter with the light head positioned 50mm from the surface. 
50mm lens: central spot approximately 5mm diameter, intensity increase ~2x. 
30mm lens: central spot approximately 2mm diameter, intensity increase ~3.5x. 

The images below show the focus lens add-on and the effect. The three illumination spot images were made in manual exposure mode and are indicative of the relative intensity.

Considerations for lens choice:

• To gain the benefit of the 30mm lens it is necessary to position the light head very close to the subject. This may be challenging in the tight space beneath a microscope objective. It might be more suited for photoactivation, where a high light intensity dose in a small area is often needed. 
• The 50mm lens provides a trade-off – brighter fluorescence, easier to work with. 

Note: If the light head has a snoot installed that will have to be removed to use the focus add-on.