Structured illumination microscope, structured illumination method, and program
A structured illumination microscope includes a spatial light modulator containing ferroelectric liquid crystals, an interference optical system for illuminating a specimen with an interference fringe generated by making lights from the spatial light modulator interfere with each other, a controller for applying a voltage pattern having a predetermined voltage value distribution to the ferroelectric liquid crystals, an image forming optical system for forming an image of the specimen, which has been irradiated with the interference fringe, an imaging element for generating an image by imaging the image formed by the image forming optical system, and a demodulating part for generating a demodulated image using a plurality of images, wherein the controller applies an image generation voltage pattern for generating the demodulated images and a burn-in prevention voltage pattern calculated based on the image generation voltage pattern to the ferroelectric liquid crystals.
1. A structured illumination microscope comprising:
a spatial light modulator;
an illumination optical system for illuminating a specimen with illumination light from the spatial light modulator;
a controller for applying a voltage pattern having a predetermined voltage value distribution to the spatial light modulator;
an image forming optical system for forming a first image of the specimen;
an imaging element for generating a second image by imaging the first image formed by the image forming optical system; and
a demodulating part for generating a demodulated image using a plurality of the second images, wherein
the controller
applies, in a first period, plural image generation voltage patterns for generating plural of the demodulated images, and
applies, in a second period different from the first period, a burn-in prevention voltage pattern for preventing burn-in generated by the plural image generation voltage patterns, and
a number of times the burn-in prevention voltage pattern is applied is less than a number of times the plural image generation voltage patterns are applied.
2. The structured illumination microscope according to claim 1 , wherein
the burn-in prevention voltage pattern is not used for generating the demodulated image.
3. The structured illumination microscope according to claim 1 , wherein
the illumination optical system illuminates the specimen with an interference fringe, and
the controller
applies the plural image generation voltage patterns in a predetermined sequence to change a phase and a direction of the interference fringe, and
applies the burn-in prevention voltage pattern before and after the change in direction of the interference fringe.
4. The structured illumination microscope according to claim 1 , wherein
the controller applies the burn-in prevention voltage pattern after changing the direction of the interference fringe at least twice.
5. The structured illumination microscope according to claim 1 , wherein
the burn-in prevention voltage pattern is calculated based on a reverse voltage of a sum voltage pattern, which is obtained by summing the plural image generation voltage patterns.
6. The structured illumination microscope according to claim 1 , wherein
the spatial light modulator includes a first substrate including a plurality of pixel electrodes, a second substrate opposing the first substrate, and liquid crystals positioned between the first substrate and the second substrate, and
the controller applies the voltage pattern to the spatial light modulator via the pixel electrodes.
7. The structured illumination microscope according to claim 6 , wherein
the liquid crystals are ferroelectric liquid crystals.
8. The structured illumination microscope according to claim 1 , wherein
the image generation voltage patterns are composed of a first voltage value having a positive electric potential and a second voltage value having a negative electric potential with a same absolute value as the first voltage value.
9. The structured illumination microscope according to claim 1 , wherein
the controller applies the burn-in prevention voltage pattern once after applying the plural image generation voltage patterns.
10. A structured illumination method comprising:
(a) illuminating a specimen with illumination light from a spatial light modulator;
(b) applying a voltage pattern having a predetermined voltage value distribution to the spatial light modulator;
(c) forming a first image of the specimen;
(d) generating a second image by imaging the first image formed in (c); and
(e) generating a demodulated image using a plurality of the second images, wherein
in (b), plural image generation voltage patterns for generating plural of the demodulated images are applied in a first period,
a burn-in prevention voltage pattern for preventing burn-in generated by the plural image generation voltage patterns is applied in a second period different from the first period, and
a number of times the burn-in prevention voltage pattern is applied is less than a number of times the plural image generation voltage patterns are applied.
11. A non-transitory computer readable medium storing a program for causing a computer to execute the steps of:
(a) illuminating a specimen with illumination light from a spatial light modulator;
(b) applying a voltage pattern having a predetermined voltage value distribution to the spatial light modulator;
(c) forming a first image of the specimen;
(d) generating a second image by imaging the first image formed in (c); and
(e) generating a demodulated image using a plurality of the second images, wherein
in (b), plural image generation voltage patterns for generating plural of the demodulated images are applied in a first period,
a burn-in prevention voltage pattern for preventing burn-in generated by the plural image generation voltage patterns is applied in a second period different from the first period, and
a number of times the burn-in prevention voltage pattern is applied is less than a number of times the plural image generation voltage patterns are applied.