Laser polarimeter at VEPP-4M collider

VEPP-4M collider and KEDR detector are going to measure precisely $\Upsilon$(1S) mass and leptonic width. In this experiment the electron beam energy is precisely measured using resonant depolarisation tecnhique at "Laser Polarimeter" facility. The electron beam polarisation degree is measured using Compton backscattering with accuracy of 5\% in 100 seconds. The beam energy is measured during KEDR data acquisition runs every 30~minutes with accuracy of 20~keV. In this report the facility design and current status are discussed.