Fluorescence observation system and set of filters

A fluorescence observation system comprising:

• a light source for illuminating an object;
• observation optics for imaging the object;
• an illumination light filter disposed in an illumination beam path between the light source and the object;
• and
• an observation light filter disposed in a beam path of the observation optics;
• wherein a transmission characteristic of the illumination light filter is a sum of a first partial characteristic and a second partial characteristic;
• wherein a transmission characteristic of the observation light filter is a sum of a third partial characteristic and a fourth partial characteristic;
• wherein the first partial characteristic has, at wavelengths below a threshold wavelength, at least one wavelength range in which the transmission has values greater than a first value;
• wherein the second partial characteristic has, at wavelengths above the threshold wavelength, at least one second wavelength range in which the transmission has values less than a second value and greater than a third value, wherein the transmission of the illumination light filter has, between the first wavelength range and the second wavelength range, values less than a fourth value;
• wherein the third partial characteristic has, at wavelengths above the threshold wavelength, at least one third wavelength range in which the transmission has values greater than the first value;
• wherein the fourth partial characteristic has, at wavelengths below the threshold wavelength, at least one fourth wavelength range in which the transmission has values less than the second value and greater than the third value, wherein the transmission of the observation light filter has, between the fourth wavelength range and the third wavelength range, values which are smaller than the fourth value;
• and
• wherein the fourth value is less than the third value, the third value is less than the second value and the second value is less than the first value.

A method of performing a fluorescence observation, wherein the method comprises:

• filtering of an illumination light beam directed to an object using an illumination light filter, and
• filtering of light emanating from the object using an observation light filter;
• wherein a transmission characteristic of the illumination light filter is a sum of a first partial characteristic and a second partial characteristic;
• wherein a transmission characteristic of the observation light filter is a sum of a third partial characteristic and a fourth partial characteristic;
• wherein the first partial characteristic has, at wavelengths below a threshold wavelength, at least one wavelength range in which the transmission has values greater than a first value;
• wherein the second partial characteristic has, at wavelengths above the threshold wavelength, at least one second wavelength range in which the transmission has values less than a second value and greater than a third value, wherein the transmission of the illumination light filter has, between the first wavelength range and the second wavelength range, values less than a fourth value;
• wherein the third partial characteristic has, at wavelengths above the threshold wavelength, at least one third wavelength range in which the transmission has values greater than the first value;
• wherein the fourth partial characteristic has, at wavelengths below the threshold wavelength, at least one fourth wavelength range in which the transmission has values less than the second value and greater than the third value, wherein the transmission of the observation light filter has, between the fourth wavelength range and the third wavelength range, values which are smaller than the fourth value;
• and
• wherein the fourth value is less than the third value, the third value is less than the second value and the second value is less than the first value.