Carbon nanotubes have promising electron emission characteristics. We report on photo-electron emitters made from sparse collections of single-walled carbon nanotubes resting on a silicon dioxide surface. A 266 nm ultraviolet laser was used. The measured emission current suggests a level of optical power absorption of approximately an order of magnitude higher than what is expected purely based on the surface area of the nanotubes; it appears that a more efficient mechanism is at work. We also present simulation results and discuss whether optical antenna effects could provide an insight.