Porous collimating mirror with long working distance

The utility model discloses a multi-hole collimating mirror with a long working distance. The multi-hole collimating mirror comprises an inlet glass tube arranged at one end; an inlet glass capillary tube is sleeved in the inlet glass tube; the outer side of the inlet glass capillary tube is connected with an inlet optical fiber; the side, located in the inlet glass tube, of the inlet glass capillary tube is connected with an inlet Cens; the inlet glass tube is fixed at one end of the porous steel tube through UV glue; the other end of the porous steel pipe is connected with an outlet glass pipe through UV glue; the outlet glass tube is positioned in the porous steel tube and is provided with an outlet Cens; the outer side of the outlet Cens is connected with an outlet glass capillary tube; and the outlet glass capillary tube is outwards connected with an outlet optical fiber. The device can be applied to the field of methane gas detection, and is simple in structure and convenient for mass production. 本实用新型公