Method and apparatus for determining the polarization properties of light emitted, reflected or transmitted by a material using a laser scanning microscope

A method for determining polarization properties of light emitted, reflected or transmitted by a material using a laser scanning microscope comprising:

• illuminating a test material point by point with a laser beam of known polarization state;
• receiving light from each illuminated point of the material, the light having a polarization state modified by the material or the light being emitted by the material;
• measuring an intensity of two different polarization components of the light received from each illuminated point of the material substantially at the same time and assigning a signal to each measured intensity;
• and
• processing the two measured intensity signals and assigning a signal to a respective point of an image of the material;
• wherein a phase between the polarization components of the light from the illuminated points is varied periodically according to a function with a predetermined frequency and shape between two end positions, and a fluorescenee detected linear dichroism value and the fluorescence detected circular dichroism value are determined by measuring the intensity of light emitted by the material periodically with a predetermined frequency (2f and f) and the phase.

A method for determining the polarization properties of light emitted, reflected or transmitted by a material using a laser scanning microscope comprising:

• illuminating a test material point by point with a laser beam of known polarization state;
• receiving light from each illuminated point of the material, the light having a polarization state modified by the material or the light being emitted by the material;
• measuring an intensity of two different polarization components of the light received from each illuminated point of the material Substantially at the Same time and assigning a signal to each measured intensity;
• and
• processing the two measured intensity signals and assigning a signal to a respective point of an image of the material;
• wherein spatially and/or temporarily concentrated laser light is used for illuminating the material and for causing two or more photon excitations in molecules of the sample.

An apparatus for determining differential polarization quantities of a test material using a laser scanning microscope comprising:

• a laser light source for generating a single beam, the single beam illuminating a test material;
• a polarization state generator disposed between a the laser light source and a the material being tested for generating a beam of known and adjustable or variable polarization state;
• a detector for determining the intensity of light with a polarization state modified by the material or intensity of light with a polarization state of light emitted by the material, the detector receiving said light;
• a means for separating different polarization components in space or time disposed between the sample and the detector;
• and
• a processing unit for processing the polarization components and for determining the differential polarization quantities of the sample.

An apparatus for determining differential polarization quantities of a test material using a laser scanning microscope comprising:

• a polarization state generator disposed between a laser light source and the material being tested;
• a detector for determining the intensity of light with a polarization state modified by the material or intensity of light emitted by the material, the detector receiving said light;
• a means for dividing polarization components in space or dine disposed in front of the detector;
• and
• a first polarization modulator in the light received from the material for dividing the polarization components in time;
• and
• a passive polarization analyzer disposed in front of the detector.

An apparatus for determining the polarization properties of light emitted, reflected or transmitted by a material using a laser scanning microscope comprising:

• a polarization state generator disposed between a laser light source and a material being tested,
• a detector for determining intensity of light with a polarization state modified by the material or intensity of light emitted by the material, the detector receiving said light;
• a means for dividing polarization components in space or time disposed in front of the detector;
• and
• the laser light Source with spatially and/or temporarily concentrated laser light for at least two photon excitation of molecules of the material.