Beamsplitters reflect a portion of the incident light and transmit the remainder.
Most often they are used at a 45º angle of incidence, but we have the capability to design beamsplitters for other angles of incidence.
For simple angular insensitive requirements, metal coatings can be used as long as a relatively large amount of absorption can be accepted. All dielectric designs can give spectrally flat transmittance and reflectance curves over about a 300nm bandwidth.
Infra-red 50:50 Beamsplitter