Super-resolution microscope

A super-resolution microscope for observing a sample containing a molecule having at least two or more excited quantum state comprising:

• an illumination optical system that condenses a first illumination light beam for exciting the molecule from a stable state to a first quantum state and a second illumination light beam for further transitioning the molecule to another quantum state onto a sample in a manner that the first illumination light beam and the second illumination light beam are partially overlapped with each other so as to irradiate the sample with the first illumination light beam and the second illumination light beam;
• a scanning section that scans the sample by relatively displacing the first illumination light beam and the second illumination light beam and the sample;
• a detection section that detects an optical response signal emitted from the sample in response to irradiation of the first illumination light beam and the second illumination light beam;
• and
• a phase plate that is arranged in an optical path of the illumination optical system through which the first illumination light beam and the second illumination light beam pass and has a plurality M of surface areas for modulating the phase of at least a portion of the second illumination light beam,
• wherein the phase plate is formed by etching an optical substrate to have the plurality M of surface areas with a thickness that satisfies the following conditional expression:
• 2
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• π
• λ
• e
• ⁢
• (
• n
• e
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• 1
• )
• ·
• d
• i
• =
• 2
• ⁢
• ⁢
• ⅈ
• ⁢
• ⁢
• π
• M
• +
• 2
• ⁢
• ⁢
• m
• i
• ⁢
• π
• 2
• ⁢
• ⁢
• π
• λ
• p
• ⁢
• (
• n
• p
• -
• 1
• )
• ·
• d
• i
• =
• Ψ
• i
• +
• 2
• ⁢
• l
• i
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• π
• 
• Ψ
• i
• 
• ≤
• π
• 4
• where di is the thickness of the substrate that remains after etching of the ith surface area, with the surface area which is the most deeply etched being a base level, λp is the first illumination light beam wavelength, λe is the second illumination light beam wavelength, np is the refractive index of the first illumination light beam in the optical substrate, ne is the refractive index of the second illumination light beam in the optical substrate, mi and li are integers characterizing the thickness of the substrate that remains after etching of the ith surface area, and Ψ represents a constant phase shift.