End reflectors are key optical components in laser resonators.They usually has high reflectance of 99.5% or 99.7%. Because absorption in the coating is higher than in the output coupler, substrate materials, such as Ge or GaAs, with high thermal conductivity are used in most lasers.

Specifications
Material	Ge or GaAs
Diameter Tolerances	+.000" , -.005"
Thickness Tolerances	±.010"
Parallelism	< 3 arc minutes
Surface Quality	< 40/20 scratch – dig Laser Finish
Spectral Performance
SIDE 1	Reflectance and tolerance listed as below
99%         ±1.0%
99.5%       ±0.2%
99.7%       ±0.1%
SIDE 2
Standard high efficiency low loss anti-reflectance
AR-coating for 10.6μm
Total finish part Absorption < .15%
Angle Of Incidence	Normal incidence (0°)

P/N	Substrate	Dia	Edge Thickness	Radius	Coating
			(mm)	Side1/Side2	Side1/Side2
RM-1024-15-99.5	GE	25.4mm	6mm	15MCC/PO	99.5%R/AR
RM-1024-18-99.5	GE	25.4mm	6mm	18MCC/PO	99.5%R/AR
RM-1122-20-99.5	GE	27.94mm	5.59mm	20MCC/PO	99.5%R/AR
RM-1122-15-0.6-99.5	GE	27.94mm	5.59mm	15MCC/0.6MCX	99.5%R/AR
RM-1124-20-99.5	GE	27.94mm	6mm	20MCC/PO	99.5%R/AR
RM-1124-30-99.5	GE	27.94mm	6mm	30MCC/PO	99.5%R/AR
RM-1224-15-99.5	GE	30mm	6mm	15MCC/PO	99.5%R/AR
RM-1224-20-99.5	GE	30mm	6mm	20MCC/PO	99.5%R/AR
RM-1224-30-99.5	GE	30mm	6mm	30MCC/PO	99.5%R/AR
RM-1532-15-99.5	GE	38.1mm	8mm	15MCC/PO	99.5%R/AR
RM-1532-20-99.5	GE	38.1mm	8mm	20MCC/PO	99.5%R/AR
RM-1532-35-99.5	GE	38.1mm	8mm	35MCC/PO	99.5%R/AR
RM-1532-51.6-99.5	GE	38.1mm	8mm	51.6MCC/PO	99.5%R/AR
RM-2038-30-99.5	GE	50.8mm	9.525mm	30MCC/PO	99.5%R/AR
RM-1124-15-0.75-99.7	GaAs	27.94mm	6mm	15MCC/0.75MCX	99.7%R/AR
RM-1124-15-29.54"-99.7	GE	27.94mm	6mm	15MCC/29.54"CX	99.7%R/AR
RM-1524-30-99.7	GaAs	38.1mm	6mm	30MCC/PO	99.7%R/AR
RM-42-6-30-99.7	GaAs	1.65"	6mm	30MCC/PO	99.7%R/AR

★The above are about standard products,they can also be custom made