Optical apparatus provided with correction collar for aberration correction and imaging method using same

An optical apparatus provided with an objective with a correction collar for correcting an aberration due to an error in an optical thickness of a sample holding member, said optical apparatus comprising:

• an optical thickness detecting unit which detects the optical thickness of the sample holding member;
• an operating unit which calculates an amount of drive of the correction collar for correcting the aberration, based on the optical thickness of the sample holding member detected by the optical thickness detecting unit;
• a driver unit which drives the correction collar, based on the amount of drive of the correction collar calculated by the operating unit;
• a focusing mechanism which changes a distance between the objective and a sample;
• and
• an image sensor which forms an image of the sample that passes through the objective,
• wherein the optical thickness detecting unit comprises a pupil-splitting length measurement instrument including:
• a light source;
• a shielding plate which shields, at a pupil-conjugate position of the objective, half of a luminous flux of beams emitted from the light source;
• the objective, which generates oblique illumination from the beam passing through the shielding plate, and which directs the oblique illumination to the sample holding member;
• and
• a two-splitting sensor which detects reflection light from the sample holding member, the two-splitting sensor being placed at a position conjugate to a focus position of the objective, and divided into a first sensor and a second sensor with respect to an optical axis,
• wherein the optical thickness detecting unit detects a first surface of the sample holding member touching the air and a second surface of the sample holding member touching the sample, based on a difference in intensity of light detected by the first and second sensors, the difference being obtained using the pupil-splitting length measurement instrument, and wherein the optical thickness detecting unit obtains the optical thickness of the sample holding member by calculating an amount of relative drive of the objective to the sample between the first and second surfaces.

An optical apparatus provided with an objective with a correction collar for correcting an aberration due to an error in an optical thickness of a sample holding member, said optical apparatus comprising:

• an optical thickness detecting unit which detects the optical thickness of the sample holding member;
• an operating unit which calculates an amount of drive of the correction collar for correcting the aberration, based on the optical thickness of the sample holding member detected by the optical thickness detecting unit;
• a driver unit which drives the correction collar, based on the amount of drive of the correction collar calculated by the operating unit;
• a focusing mechanism which changes a distance between the objective and a sample;
• and
• an image sensor which forms an image of the sample that passes through the objective,
• wherein the optical thickness detecting unit comprises a pupil-splitting length measurement instrument including:
• a light source;
• a shielding plate which shields, at a pupil-conjugate position of the objective, half of a luminous flux of beams emitted from the light source;
• the objective, which generates oblique illumination from the beam passing through the shielding plate, and which directs the oblique illumination to the sample holding member;
• and
• a two-splitting sensor which detects reflection light from the sample holding member, the two-splitting sensor being placed at a position conjugate to a focus position of the objective, and divided into a first sensor and a second sensor with respect to an optical axis,
• wherein the optical thickness detecting unit (i) detects a first surface touching the air of the sample holding member based on a difference in intensity of light detected by the first and second sensors, the difference being obtained using the pupil-splitting length measurement instrument, (ii) detects a second surface touching the sample of the sample of the sample holding member by focusing on the sample with a contrast detection method, and (iii) obtains the optical thickness of the sample holding member by calculating an amount of relative drive of the objective to the sample between the first and second surfaces.

An optical apparatus provided with an objective with a correction collar for correcting an aberration due to an error in an optical thickness of a sample holding member, said optical apparatus comprising:

• an optical thickness detecting unit which detects the optical thickness of the sample holding member;
• an operating unit which calculates an amount of aberration correction, based on the optical thickness of the sample holding member detected by the optical thickness detecting unit;
• a driver unit which drives the correction collar, based on the amount of aberration correction calculated by the operating unit;
• a focusing mechanism which changes a distance between the objective and a sample;
• and
• an image sensor which forms the image of the sample that passes through the objective,
• wherein the optical thickness detecting unit comprises:
• a mechanical thickness detecting unit which detects a mechanical thickness of the sample holding member;
• and
• a refractive index identifying unit which identifies a refractive index of the sample holding member;
• wherein the optical thickness of the sample holding member is calculated based on the mechanical thickness and the refractive index of the sample holding member.

An optical apparatus provided with an objective with a correction collar for correcting an aberration due to an error in an optical thickness of a cover glass, said optical apparatus comprising:

• a focusing mechanism which changes a distance between the objective and a sample;
• an optical thickness detecting unit which detects the optical thickness of the cover glass;
• an operating unit which calculates an amount of drive of the correction collar for correcting the aberration, based on the optical thickness of the cover glass detected by the optical thickness detecting unit;
• a driver unit which drives the correction collar, based on the amount of drive of the correction collar calculated by the operating unit;
• and
• an image sensor which forms the image of the sample that passes through the objective,
• wherein:
• the focusing mechanism detects a first focus position on which an objective side surface of the cover glass is focused and a second focus position on which a sample surface of the cover glass is focused,
• the optical thickness detecting unit calculates the optical thickness of the cover glass based on a difference between the first and second focus positions,
• the operating unit calculates the amount of drive of the correction collar based on the difference between the first and second focus positions obtained by the focusing mechanism, and
• the driver unit drives the correction collar based on the amount of drive of the correction collar calculated by the operating unit.

A method for imaging a sample using an optical apparatus provided with an objective with a correction collar for correcting an aberration due to an error in an optical thickness of a sample holding member, the method comprising:

• detecting the optical thickness of the sample holding member by using a pupil-splitting length measurement instrument including (i) a light source, (ii) a shielding plate which shields, at a pupil-conjugate position of the objective, half of a luminous flux of beams emitted from the light source, (iii) the objective, which generates oblique illumination from the beam passing through the shielding plate, and which directs the oblique illumination to the sample holding member, and (iv) a two-splitting sensor which detects reflection light from the sample holding member, the two-splitting sensor being placed at a position conjugate to a focus position of the objective, and divided into a first sensor and a second sensor with respect to an optical axis;
• calculating an amount of drive of the correction collar for correcting the aberration, based on the detected optical thickness;
• driving the correction collar, based on the calculated amount of drive of the correction collar;
• changing a distance between the objective and a sample;
• and
• forming an image of the sample that passes through the objective.

A method for imaging a sample using an optical apparatus provided with an objective with a correction collar for correcting an aberration due to an error in an optical thickness of a sample holding member, the method comprising:

• detecting the optical thickness of the sample holding member;
• calculating an amount of drive of the correction collar for correcting the aberration, based on the detected optical thickness;
• driving the correction collar, based on the calculated amount of drive of the correction collar;
• changing a distance between the objective and a sample;
• and
• forming an image of the sample that passes through the objective,
• wherein the detecting of the optical thickness of the sample holding member is carried out using a pupil-splitting length measurement instrument,
• wherein the pupil-splitting length measurement instrument includes:
• (i) a light source, (ii) a shielding plate which shields, at a pupil-conjugate position of the objective, half of a luminous flux of beams emitted from the light source, (iii) the objective, which generates oblique illumination from the beam passing through the shielding plate, and which directs the oblique illumination to the sample holding member, and (iv) a two-splitting sensor which detects reflection light from the sample holding member, the two-splitting sensor being placed at a position conjugate to a focus position of the objective, and divided into a first sensor and a second sensor with respect to an optical axis;
• and
• wherein the detecting of the optical thickness of the sample holding member comprises:
• detecting a first surface of the sample holding member touching the air and a second surface of the sample holding member touching the sample, based on a difference in intensity of light detected by the first and second sensors, and
• calculating an amount of relative drive of the objective to the sample between the first and second surfaces,
• wherein the difference in intensity of light detected by the first and second sensors is obtained by utilizing the pupil-splitting length measurement instrument.

A method for imaging a sample using an optical apparatus provided with an objective with a correction collar for correcting an aberration due to an error in an optical thickness of a sample holding member, the method comprising:

• detecting the optical thickness of the sample holding member;
• calculating an amount of drive of the correction collar for correcting the aberration, based on the detected optical thickness;
• driving the correction collar, based on the calculated amount of drive of the correction collar;
• changing a distance between the objective and a sample;
• and
• forming an image of the sample that passes through the objective,
• wherein the detecting of the optical thickness of the sample holding member is carried out using a pupil-splitting length measurement instrument,
• wherein the pupil-splitting length measurement instrument includes:
• (i) a light source, (ii) a shielding plate which shields, at a pupil-conjugate position of the objective, half of a luminous flux of beams emitted from the light source, (iii) the objective, which generates oblique illumination from the beam passing through the shielding plate, and which directs the oblique illumination to the sample holding member, and (iv) a two-splitting sensor which detects reflection light from the sample holding member, the two-splitting sensor being placed at a position conjugate to a focus position of the objective, and divided into a first sensor and a second sensor with respect to an optical axis;
• and
• wherein the detecting of the optical thickness of the sample holding member comprises:
• detecting a first surface of the sample holding member touching the air based on a difference in intensity of light detected by the first and second sensors,
• focusing the sample so as to detect a second surface of the sample holding member touching the sample by a contrast detection method, and
• calculating an amount of relative drive of the objective to the sample between the first and second surfaces,
• wherein the difference in intensity of light detected by the first and second sensors is obtained by utilizing the pupil-splitting length measurement instrument.

A method for imaging a sample using an optical apparatus provided with an objective with a correction collar for correcting an aberration due to an error in an optical thickness of a sample holding member, the method comprising:

• detecting the optical thickness of the sample holding member;
• calculating an amount of aberration correction, based on the optical thickness;
• driving the correction collar, based on the amount of aberration correction;
• changing a distance between the objective and a sample;
• and
• forming an image of the sample that passes through the objective,
• wherein the detecting of the optical thickness of the sample holding member comprises:
• detecting a mechanical thickness of the sample holding member, and
• detecting a refractive index of the sample holding member.