The speaker has left their glasses behind and describes how strange and unsettling the world becomes without them. Trees turn into blurs, crowds into blotches of color, and faces into "color blobs" sitting on top of bodies. With sight dulled, the other senses seem to swell: everything feels louder, and smells grow sharper. The speaker is not fully blind, but the loss of detail is enough to make ordinary life feel uncertain and a little frightening.
The ending shifts the mood. The line "To have my glass is to have sight / To have forgotten to have freedom from fright" suggests that clear vision means safety, and that forgetting the glasses has taken that away. Calling the glasses a "lock and key" is interesting, since they both confine the speaker and give access to the world. The final line, "Watching, waiting, for something to come to me," leaves a feeling of helpless suspense. The speaker can only stand in the haze and wait, anxious and exposed, for the world to come into focus.