how i can test a LCD

how i can test an LCD to know that its working or not. i don't want to test it in circuit. are there any way. it is ts1620a-21\b. its good to say that when it is in the circuit only the half down part of it are completely turns on. can any body tell me what is the cause of it?

You have to connect it to a known working circuit to test it, there is no other way.

If you only have half of the screen turned on that's because it's been initialized for single line display. Read the PDF it explains how to properly initialize the display.