Surface-plasmon microscopy with a two-piece solid immersion lens: bright and dark fields.

We report bright-field and dark-field surface-plasmon imaging using a modified solid immersion lens and a commercial objective of moderate NA in the epi configuration. The contrast and resolution are extremely good, giving well-resolved images of protein monolayers both in air and in water. We also describe a two-part solid immersion lens that allows the sample to be moved without degrading the image quality in any observable way.