Germanium Lens Advantage

I read at Edmund Scientific that Germanium is refractive index 4.
This was the highest index material in the list.
Than I looked to the price lists and 3 element , 3 centimeters diameter lens is 140 dollars.
Do these lenses make a killer image quality or waste of time ?
Is there extremelly high abbe number , high ref index doublet or triplet lenses at the market ? May be Schott start to make Lutetium at near future .

Thank you ,

Mustafa Umut Sarac

Istanbul

I think germanium is for infrared imaging only. I don't think it is transparent to visible light.

Thank you.

alanrockwood said:

I don't think it is transparent to visible light.

Click to expand...

correct.