Patent ID: 6844963

Claim:
A double-resonance absorption microscope, comprising: a pump light source for emitting a pump light having a wavelength λ 1 so as to excite a sample molecule from a ground state to a first electronic excited state; an erase light source for emitting an erase light having a wavelength λ 2 so as to excite the sample molecule from the first electronic excited state to at least a second electronic excited state; an overlap component for partially overlapping irradiating areas of the pump light and the erase light with each other so that an emission area is partially inhibited during de-excitation of the sample molecule from the first electronic excited state to the ground state by irradiating the pump light and the erase light through said overlap component; a spatial filter located on an optical path of the erase light to be emitted from said erase light source, said spatial filter including a condenser lens, a collimate lens, and a pinhole located between said condenser lens and said collimate lens, wherein said condenser lens, said collimate lens, and said pinhole are arranged so as to condense the erase light into said pinhole, to collimate the erase light having passed through said pinhole into a parallel beam, and to suppress wavefront disturbance of the erase light; and a phase modulation element for providing the erase light having passed through said spatial filter with a phase difference of π around an optical axis of the erase light so as to produce a first-order Bessel beam.