Observation vessel, sample preparation method, and observation method
An observation vessel includes a holding portion configured to hold an observation object and an accommodation portion at least partially formed of a transparent curved surface and configured to position the holding portion. The holding portion is configured to hold the observation object at a set position separated from the curved surface toward a center of curvature of the curved surface in a first state of being positioned at a first position by the accommodation portion.
1. An observation vessel comprising:
a holding portion configured to hold an observation object; and
an accommodation portion that is at least partially formed of a bottom having a transparent three-dimensional curved surface and is configured to position the holding portion,
wherein the holding portion is configured to hold the observation object at a set position separated from the three-dimensional curved surface toward a center of curvature of the three-dimensional curved surface inside the accommodation portion in a first state of being positioned at a first position by the accommodation portion, and
wherein the observation vessel is configured to guide light from the observation object held at the set position into an objective lens positioned below the bottom of the accommodation portion via the three-dimensional curved surface,
wherein the three-dimensional curved surface and a positional relationship between the set position and the three-dimensional curved surface suppresses spherical aberration caused by refractive index mismatching between the observation vessel and a medium in the observation vessel or between the medium in the observation vessel and an immersion liquid between the observation vessel and the objective lens.
2. The observation vessel according to claim 1 , wherein
the holding portion is configured to hold, in the first state, the observation object at the set position by suspending a gel or a solid in which the observation object is embedded.
3. The observation vessel according to claim 2 , wherein
the holding portion includes a hanging drop forming portion configured to form a hanging drop of a medium solution containing the observation object,
the hanging drop contains the observation object that moves to a predetermined relative position with respect to the holding portion due to a component force of gravity acting along a liquid surface, and
the gel or the solid is formed by gelation or solidification of the hanging drop.
4. The observation vessel according to claim 2 , wherein
the gel or the solid is a medium solution accommodated in the accommodation portion, and is formed by gelation or solidification of a medium solution containing the observation object that moves to a predetermined relative position with respect to the holding portion due to a component force of gravity acting along the curved surface, and
the holding portion further serves as a peeling portion configured to peel the gel or the solid from the curved surface by sliding in the accommodation portion.
5. The observation vessel according to claim 4 , wherein
the accommodation portion includes:
a first locking portion configured to position the holding portion at the first position; and
a second locking portion configured to position the holding portion at a second position,
the holding portion being configured to hold the observation object, which is embedded in the gel or the solid, on the curved surface in a second state of being positioned at the second position by the accommodation portion.
6. The observation vessel according to claim 1 , wherein
the holding portion includes a recess configured to hold the observation object, and
the holding portion is arranged or formed on the curved surface in a state where the recess faces vertically upward.
7. The observation vessel according to claim 6 , wherein
the holding portion is made of silicone rubber.
8. The observation vessel according to claim 6 , wherein
the holding portion is formed by an absorbent polymer arranged in the accommodation portion to absorb water and expand.
9. The observation vessel according to claim 1 , wherein
the accommodation portion is at least partially formed of a transparent flat surface, and
the set position is located on a normal line of the flat surface.
10. The observation vessel according to claim 1 , wherein the curved surface is a spherical surface.
11. The observation vessel according to claim 1 , wherein the curved surface has a predetermined curvature.
12. The observation vessel according to claim 1 , wherein
when a distance from the curved surface to the observation object held at the set position is defined as d and a radius of curvature of the curved surface is defined as R, a following conditional expression is satisfied:
R/ 2 <d<R (1).
13. The observation vessel according to claim 1 , wherein
the observation vessel includes a plurality of elements arranged one-dimensionally or two-dimensionally, and
each of the plurality of elements includes the accommodation portion and the holding portion.
14. A method using an observation vessel including a holding portion that is configured to hold an observation object, and an accommodation portion that is at least partially formed of a bottom having a transparent three-dimensional curved surface and is configured to position the holding portion, the method comprising:
positioning the holding portion at a first position by the accommodation portion;
holding the observation object at a set position separated from the three-dimensional curved surface toward a center of curvature of the three-dimensional curved surface inside the accommodation portion in a first state where the holding portion is positioned at the first position; and
guiding light from the observation object held at the set position into an objective lens positioned below the bottom of the accommodation portion via the three-dimensional curved surface;
wherein the three-dimensional curved surface and a positional relationship between the set position and the three-dimensional curved surface suppresses spherical aberration caused by refractive index mismatching between the observation vessel and a medium in the observation vessel or between the medium in the observation vessel and an immersion liquid between the observation vessel and the objective lens.
15. The method according to claim 14 , further comprising:
forming a hanging drop of a medium solution containing the observation object by the holding portion; and
forming a gel or a solid, in which the observation object is embedded, by gelation or solidification of the hanging drop,
wherein
the holding the observation object at the set position in the first state includes suspending the gel or the solid in which the observation object is embedded.
16. The method according to claim 14 , further comprising:
covering the curved surface with a medium solution containing the observation object poured into the accommodation portion;
forming a gel or a solid, in which the observation object is embedded, by gelation or solidification of the medium solution; and
peeling the gel or the solid from the curved surface,
wherein
the holding the observation object at the set position in the first state includes suspending the gel or the solid in which the observation object is embedded.
17. The method according to claim 14 , further comprising:
covering a recess of the holding portion positioned at the first position with a medium solution containing the observation object poured into the accommodation portion,
wherein
the positioning the holding portion at the first position includes arranging or forming the holding portion on the curved surface in a state where the recess faces vertically upward, and
the holding the observation object at the set position in the first state includes holding the observation object in the recess.
18. The method according to claim 15 , further comprising:
filling a space between the accommodation portion and the objective lens with the immersion liquid.