In an image display device which employs pulse width modulation driving, a voltage which is less than a voltage supplied to signal lines is applied to pixel electrodes. The particles are introduced from the outside into the vacuum chamber of the magnetron or plasmatron via at least one pressure stage. The cinch has a portion of a pair of closable jaws squeezably arranged therewithin. The present device is particularly useful in a clinical drug of abuse testing setting, in which the use of internal quality controls is regulated by the USCMS and the College of American Pathologists. Consequently, the present invention enables to produce a semiconductor laser of a surface emitting type easier by far compared with a conventional invention.