A block arrangement of optical elements for a lidar system

A block arrangement of optical elements is provided for use as a transmitter/receiver for a light detection and ranging (LIDAR) system. The block arrangement comprises: a plurality of glass modules aligned together as a block to form a plurality of optical paths therein and secured together to maintain said alignment; a collimated light source secured to said block for generating a coherent beam of light over at least one optical path in said block which guides said coherent beam of light to an exit point of said block; and a light detector secured to said block. The block serves for receiving a return coherent beam of light and is configured to conduct said return coherent beam of light to the light detector over at least one other optical path formed in said block.