An experimental investigation of eight optogalvanio spectral lines of ArII in an HOD lamp is reported. The emission fluorescence and laser-induced fluorescence in HCL are observed. An empirical formula to explain the dominant mechanism of optogalvanio effect in HOL is proposed. We find that the discharge current iM at which the VOGE reaches maximum is relative to EH the upper energy level of the optogalvanio Spectral line.