公开(公告)号：US3617804A

公开(公告)日：1971-11-02

申请号：US3617804D

申请日：1969-10-14

Applicant: NASA

Inventor： LIBBY WILLARD F ,  JENSEN CARL A ,  WOOD LOWELL L

IPC: H01S3/03 ,  H05H1/24 ,  H01J61/16 ,  H01J61/28 ,  H01J61/78

CPC classification number: H01S3/03

Abstract: A light source apparatus for producing intense monochromatic light from a low-temperature plasma is disclosed. The light source apparatus comprises a housing member for confining a gas at subatmospheric pressure, the housing containing output means disposed to transmit light from the confined gas. At least one anode and one cathode are positioned within the gas in electrical circuit relationship with each other. First control means are provided for controlling the voltage applied to the anode and second control means independently control the temperature of the cathode by regulating the power supplied to it. The pressure of the gas is controlled by a third control means. An intense monochromatic light output is achieved by confining the gas in said chamber at a controlled predetermined reduced pressure, independently controlling the temperature of the electron emitting cathode by means of said second control means and applying a predetermined controlled low voltage to said anode by said first control means. An intermediate mode current is drawn from said cathode and produces in the confined gas a region having a high density of metastable atomic states. A lowtemperature, high-density plasma is continuously produced in said region and intense monochromatic light is emitted as a result of the recombination of ions and electrons in said plasma.