Monitoring the optical pulses from mode‐locked and synchronously pumped continuous wave (cw) lasers, reference beams are taken from the main beams with beam splitters. Depending on the angle with respect to the incident beam and the direction of the rotation axis of the beam splitter, light fractions of different polarizations can be selected. Based on practical and theoretical considerations an alternative beam‐splitter mount has been designed which efficiently utilizes the available optical power.