What is significant about the lighting used in The Glass Menagerie? What effects does it create?
The subdued lighting creates a mood of intimacy, necessary for the confessional nature of the narration of the story. It also shows the subjective nature of Tom's interpretation of past events, which he readily admits are not truly representative of reality but are rather his memories (which have become fragmented and distorted over time).
Williams uses both lighting and music for effect. For example, when Amanda dresses up Laura before meeting Jim, she tells her to make a wish on the moon, much as a lucky star. This is in sharp contrast with the scene where the lights go out just as the family is sitting down to dinner with their guest because Tom had failed to pay the electricity bill. Amanda restores the mood of nostalgia and romance by lighting a candalabra. This mood continues until Jim's confession that he already has a girl, even if he breaks the news to Laura ever so gently. The accidental breaking of the crystal unicorn figurine coincides perfectly with Laura's realization that her prince will not come; it is the shattering of a fragile illusion to return to the hard glare of reality, as Jim bows out and says goodbye.
The lighting in the very last scene is significant in that Jim "orders" Laura to blow out her light, which she does. This is the abrupt end of the play and the best way to illustrate Tom's rupture with his past. He never fully escapes, though, as the memories of his sister follow him and haunt him still.