Microscope illumination device and microscope
A microscope illumination device includes a white LED light source, and an illumination optical system that includes an aperture stop on a plane on which light from the white LED light source is condensed. The white LED light source includes a board, a plurality of LED chips that are arranged on the board and that each emit excitation light, and a phosphor layer that is provided so as to cover the plurality of LED chips and that includes at least three types of phosphors. The plurality of LED chips are arranged so as to be projected into an aperture of the aperture stop.
1. A microscope illumination device comprising:
a white LED light source that includes a board, a plurality of LED chips that are arranged on the board and each of which is configured to emit excitation light, and a phosphor layer that is provided so as to cover the plurality of LED chips and that includes at least three types of phosphors; and
an illumination optical system that includes an aperture stop on a plane on which light from the white LED light source is condensed,
wherein:
the plurality of LED chips are arranged so as to be projected into an aperture of the aperture stop when the aperture stop is in a fully open state; and
when φ LED is a diameter of a circle inscribed in the phosphor layer, MG is a magnification of an image of the white LED light source that is projected onto the plane on which the aperture stop is located, φ AS is an aperture diameter of the aperture stop in the fully open state, and R is a diameter of a minimum circle including the plurality of LED chips, conditional expressions (1) and (2) below are satisfied:
0.7≤(φ LED ×MG/φ AS ≤1.5 (1); and
0.3≤ R/φ LED (2).
2. The microscope illumination device according to claim 1 , wherein:
each of the plurality of LED chips is configured to emit the excitation light in a near-ultraviolet wavelength region; and
each of the at least three types of phosphors is a phosphor that generates fluorescence in a visible wavelength region.
3. The microscope illumination device according to claim 2 , wherein:
when φ 2 is an aperture diameter of the aperture stop in a state in which an aperture size of the aperture stop is minimized, and P is a minimum space between centers of the plurality of LED chips, conditional expression (3) below is satisfied:
0.25≤φ 2 /( P×MG )≤2 (3); and
the center of at least one LED chip of the plurality of LED chips is projected into the aperture of the aperture stop in the state in which the aperture size of the aperture stop is minimized.
4. The microscope illumination device according to claim 3 , wherein the plurality of LED chips are arranged in M rows and N columns (M and N are respective integers of 4 or more) on the board.
5. The microscope illumination device according to claim 3 , wherein the plurality of LED chips are arranged concentrically with an optical axis of the illumination optical system as a center on the board.
6. The microscope illumination device according to claim 2 , wherein the plurality of LED chips are arranged in M rows and N columns (M and N are respective integers of 4 or more) on the board.
7. The microscope illumination device according to claim 2 , wherein the plurality of LED chips are arranged concentrically with an optical axis of the illumination optical system as a center on the board.
8. The microscope illumination device according to claim 1 , wherein:
when φ 2 is an aperture diameter of the aperture stop in a state in which an aperture size of the aperture stop is minimized, and P is a minimum space between centers of the plurality of LED chips, conditional expression (3) below is satisfied:
0.25≤φ 2 /( P×MG )≤2 (3); and
the center of at least one LED chip of the plurality of LED chips is projected into the aperture of the aperture stop in the state in which the aperture size of the aperture stop is minimized.
9. The microscope illumination device according to claim 8 , wherein the plurality of LED chips are arranged in M rows and N columns (M and N are respective integers of 4 or more) on the board.
10. The microscope illumination device according to claim 8 , wherein the plurality of LED chips are arranged concentrically with an optical axis of the illumination optical system as a center on the board.
11. The microscope illumination device according to claim 1 , wherein the plurality of LED chips are arranged in M rows and N columns (M and N are respective integers of 4 or more) on the board.
12. The microscope illumination device according to claim 1 , wherein the plurality of LED chips are arranged concentrically with an optical axis of the illumination optical system as a center on the board.
13. A microscope comprising:
the microscope illumination device according to claim 1 .
14. A microscope illumination device comprising:
a white LED light source that includes a board, a plurality of LED chips that are arranged on the board and that each emit excitation light, and a phosphor layer that is provided so as to cover the plurality of LED chips and that includes at least three types of phosphors; and
an illumination optical system that includes an aperture stop on a plane on which light from the white LED light source is condensed,
wherein:
the plurality of LED chips are arranged so as to be projected into an aperture of the aperture stop when the aperture stop is in a fully open state; and
when MG is a magnification of an image of the white LED light source projected onto the plane on which the aperture stop is located, φ AS is an aperture diameter of the aperture stop in the fully open state, φ 2 is an aperture diameter of the aperture stop in a state in which an aperture size of the aperture stop is minimized, R is a diameter of a minimum circle including the plurality of LED chips, S 1 is an area of one LED chip of the plurality of LED chips, and S 0 is a sum of the areas of the plurality of LED chips, conditional expressions (4), (5), and (6) below are satisfied:
0.25≤( S 1× MG )/(π×(φ 2 /2) 2 )≤1 (4);
0.1≤ S 0/(π×( R/ 2) 2 ) (5); and
0.03≤( S 0× MG )/(π×(φ AS /2) 2 )≤0.15 (6).