Microscope including remote focusing system

A microscope comprising:

• an illumination arm aligned along an illumination axis and comprising:
• a light source configured to provide a light sheet that is projected through a biological sample;
• and
• an illumination objective configured to receive the light sheet from the light source and focus the light sheet through the sample;
• and
• a detection arm comprising a detection objective comprising an optical axis that is orthogonal to the illumination axis, wherein the detection objective is configured to receive light emitted by a portion of the sample that is illuminated with the light sheet and form an unpolarized light beam that is representative of an image of the portion of the sample, wherein the detection arm further comprises a remote focusing system comprising:
• a polarizing beam splitter configured to split the unpolarized light beam that is incident upon the beam splitter from the detection objective into a first polarized light beam comprising a first polarization and a second polarized light beam comprising a second polarization, wherein the first polarization is different from the second polarization;
• a remote objective configured to focus the first polarized light beam and the second polarized light beam onto a focal plane;
• a first mirror configured to direct the first polarized light beam to the remote objective;
• a second mirror configured to direct the second polarized light beam to the remote objective;
• a focal plane mirror disposed at the focal plane of the remote objective and along an optical axis that extends orthogonally from a reflective surface of the mirror to the polarizing beam splitter, wherein the remote objective is further configured to provide a first polarized intermediate image of the portion of the sample based on the first polarized light beam on the reflective surface and a second polarized intermediate image of the portion of the sample based on the second polarized light beam on the reflective surface;
• wherein the focal plane mirror is configured to direct a third polarized light beam comprising a third polarization and representative of the first polarized intermediate image to the first mirror and a fourth polarized light beam comprising a fourth polarization and representative of the second polarized intermediate image to the second mirror, wherein the third polarization is different from the fourth polarization;
• wherein the first mirror is further configured to direct the third polarized light beam through the polarizing beam splitter to a detection surface of a detector, and further wherein the second mirror is further configured to direct the fourth polarized light beam through the polarizing beam splitter to the detection surface of the detector;
• and
• wherein the detector is configured to detect the first polarized intermediate image and the second polarized intermediate image as a final composite image.

A method comprising:

• splitting an unpolarized light beam that is incident upon a beam splitter into a first polarized light beam comprising a first polarization and a second polarized light beam comprising a second polarization, wherein the first polarization is different from the second polarization, and further wherein the unpolarized light beam is representative of an image of a portion of a biological sample;
• directing the first polarized light beam to a remote objective utilizing a first mirror;
• directing the second polarized light beam to the remote objective utilizing a second mirror;
• focusing the first polarized light beam to a reflective surface of a focal plane mirror utilizing the remote objective to provide a first polarized intermediate image of the portion of the sample;
• focusing the second polarized light beam to the reflective surface of the focal plane mirror utilizing the remote objective to provide a second polarized intermediate image of the portion of the sample;
• directing a third polarized light beam comprising a third polarization and representative of the first polarized intermediate image to the first mirror utilizing the focal plane mirror;
• directing a fourth polarized light beam comprising a fourth polarization and representative of the second polarized intermediate image to the second mirror utilizing the focal plane mirror, wherein the third polarization is different from the fourth polarization;
• directing the third polarized light beam through the polarizing beam splitter to a detection surface of a detector utilizing the first mirror;
• directing the fourth polarized light beam through the polarizing beam splitter to the detection surface of the detector utilizing the second mirror;
• and
• detecting a final composite image of the portion of the biological sample utilizing the detector, wherein the final composite image comprises the first and second polarized intermediate images.