Patent ID: 6876789

Claim:
An optical filtering module comprising: an optical filter for at least one of transmitting, attenuating and reflecting light having a certain wavelength range, a first optical system having an optical fiber for guiding light to be transferred to said optical filter, a second optical system having an optical fiber for guiding light transferred from said optical filter, said second optical system being opposingly arranged to said first optical system while interposing said optical filter therebetween, and an outer cylindrically shaped glass holder for holding therein said optical filter, said first optical system and said second optical system secured thereto, wherein each of said first and second optical systems comprises a lens optically connecting said optical fiber and said optical filter respectively, said optical filter being secured to one of said lenses of said first and second optical systems, each of said first and second optical systems comprises an optical fiber holder having a through hole for receiving said optical fiber inserted therein, each of said first and second optical systems comprises an inner holder for holding said optical fiber holder and said lens, said inner holders being secured to said outer holder with a photo-curing adhesive, and said optical fiber holder and lens are each directly secured to said inner holder.