Beamsplitter plate is an optical window with semi-transparent mirrored coating to break a beam into two separate beams. A beamsplitter will reflect a portion of the incident energy, abs..

Specifications:

Material: -----------------------------------BK7 grade A, optical glass 
Dimension Tolerance:-----------------------------------------±0.2mm 
Thickness Tolerance: -----------------------------------------±0.2mm 
Flatness: ----------------------------------------------- λ /4 @ 632.8 nm 

Surface Quality: --------------------------------60/40 scratch and dig 
Parallelism: -----------------------------------------------<1 arc minute    
T/R:-------------------------------50/50±5%, for random polarization 
        -----------------------------------------T=(Ts+Tp)/2, R=(Rs+Rp)/2 
Coatings: (Incidence angle: 45 degree) 
Surface1: ---------------------Single wavelength partial reflectance 
Surface2: -------------------------------------------------------AR-coating 
Standard Coating wavelength: 
Narrow Band: ---------488, 532, 632.8, 650, 808, 850, 980, 1064, 1310, 1550 nm 
Broadband: -------------450-650, 650-900, 900-1200, 1200-1550, 1500-1610 nm

Standard Size: