active vs. passive voice

[Michelle Vina-Baltsas]

I've read many threads on this listserv related to the use of "appears" 
vs. "displays" or "is displayed". During a meeting yesterday, with my 
fellow tech writers, we had a heated discussion about whether we should 
use "is displayed" or "displays" when writing a result (For example, 
"Select the XYZ button. The EXY dialog box is displayed.") One writer 
insisted that the use of  "is displayed" should not be used because it is 
in the passive voice. To be honest, my head was spinning so quickly that I 
decided to refrain from offering my opinion. I did tell them I'd 
investigate though. 

Is the use of "is displayed" passive voice?

Thank you,
Michelle