Abstract
NTT Photonics Laboratories have developed KTN (KTa_<1-x>Nb_xO_3) single crystal and its growth technology, thus enabling us to produce a high quality lens material applicable to a solid immersion lens. The refractive index of KTaO_3 is 2.382 at 405nm. We also confirm that the fluctuation in the birefringence in the KTaO_3 crystal is sufficiently small to meet the SIL specification. In addition, we have successfully prepared KTN crystal with the highest electro-optic effect ever reported. Now we are starting up new business relating KTN optical devices.
