Patent ID: 6841888

Claim:
An encapsulant for an opto-electronic device or optical component, the encapsulant characterized by a coefficient of thermal expansion and an optical transmittance, the encapsulant comprising: 1) a filler consisting essentially of glass particles having diameters in the range of 1 μm to 500 μm, the glass particles formed from a glass essentially free of titania and characterized by a glass refractive index having a value in the range of 1.48 to 1.60 and a variance of less than about 0.001, wherein the filler is characterized by a filler refractive index; and 2) an epoxy, characterized by an epoxy refractive index; wherein the coefficient of thermal expansion of the encapsulant has an average value of less 50 ppm/° C., with a variation of less than ±30%, and wherein the filler refractive index and the epoxy refractive index have values sufficiently similar such that the optical transmittance of the encapsulant is at least 65% when measured at a wavelength in the range of 300 nm to 800 nm at an encapsulant thickness of about 1 mm.