Observation system and observation device

1. An observation comprising:

a mounting table on which a sample container is placed;

a surface light source disposed in one of two regions divided by the mounting table, the surface light source having a light emitting plane;

an observation optical system disposed in another one of the two regions;

a conveyance mechanism configured to move the observation optical system in a direction orthogonal to an optical axis of the observation optical system to change an observation position at which a bottom surface of a housing portion of the sample container and the optical axis intersect; and

a controller comprising hardware, the controller being configured to control a light emission pattern defined by a light emitting region where light is emitted on the light emitting plane,

wherein the controller executes:

first light emission pattern control in which the light emission pattern is changed according to the observation position, or, alternatively,

second light emission pattern control in which the light emission pattern is switched between a plurality of periodic light emission patterns having phases different from each other; and

the first light emission pattern control so as to change at least one of a position and a width of the light emitting region according to the observation position; and

in a case where a part of an end of the light emitting region closest to the optical axis is located in a positive region, a conditional expression for the light emitting region

0.2 NA< S min <0.9 NA  (1)

is satisfied, and

in a case where the part of the end of the light emitting region closest to the optical axis is located in a negative region, a conditional expression for the light emitting region

−0.9 NA< S max <−0.2 NA  (3)

is satisfied,

where S min represents a sine of an incident angle of illumination light from one end of the light emitting region to the observation position, S max represents a sine of an incident angle of illumination light from another end of the light emitting region located on a positive side with respect to the one end to the observation position, and NA represents a numerical aperture on an object side of the observation optical system.

2. The observation system according to claim 1 , wherein

in a case where the part of the end of the light emitting region closest to the optical axis is located in the positive region, a conditional expression for the light emitting region

NA<S max <1  (2)

is satisfied, and

in a case where the part of the end of the light emitting region closest to the optical axis is located in the negative region, a conditional expression for the light emitting region

−1< S min <−NA   (4)

is satisfied.

3. An observation comprising:

a mounting table on which a sample container is placed;

a surface light source disposed in one of two regions divided by the mounting table, the surface light source having a light emitting plane;

an observation optical system disposed in another one of the two regions;

a conveyance mechanism configured to move the observation optical system in a direction orthogonal to an optical axis of the observation optical system to change an observation position at which a bottom surface of a housing portion of the sample container and the optical axis intersect; and

a controller comprising hardware, the controller being configured to control a light emission pattern defined by a light emitting region where light is emitted on the light emitting plane,

wherein the controller executes:

first light emission pattern control in which the light emission pattern is changed according to the observation position, or, alternatively,

second light emission pattern control in which the light emission pattern is switched between a plurality of periodic light emission patterns having phases different from each other;

wherein the light emitting region corresponding to each of the plurality of periodic light emission patterns includes a plurality of fringe regions aligned in a first direction at regular intervals,

the controller executes the second light emission pattern control so as to sequentially switch the light emission pattern to the plurality of periodic light emission patterns; and

conditional expressions

2

⁢

NA

1

-

N

⁢

A

2

<

P

-

d

H

(

9

)

0

<

❘

"\[LeftBracketingBar]"

δ

❘

"\[RightBracketingBar]"

H

<

NA

1

-

N

⁢

A

2

(

10

)

are satisfied,

where NA represents a numerical aperture on an object side of the observation optical system, P represents a pitch of the plurality of fringe regions, d represents a width of each of the plurality of fringe regions, H represents an air-converted length of a distance between the light emitting plane and the observation position, and δ represents a distance on the light emitting plane corresponding to a phase difference between the plurality of periodic light emission patterns.

4. The observation system according to claim 3 , wherein

a conditional expression

0

<

d

H

<

N

⁢

A

1

-

N

⁢

A

2

(

11

)

is satisfied.

5. The observation system according to claim 4 , wherein

a conditional expression

❘

"\[LeftBracketingBar]"

δ

❘

"\[RightBracketingBar]"

=

P

N

(

12

)

is satisfied,

where N is an integer of 1 or more.

6. An observation comprising:

a mounting table on which a sample container is placed;

a surface light source disposed in one of two regions divided by the mounting table, the surface light source having a light emitting plane;

an observation optical system disposed in another one of the two regions;

a conveyance mechanism configured to move the observation optical system in a direction orthogonal to an optical axis of the observation optical system to change an observation position at which a bottom surface of a housing portion of the sample container and the optical axis intersect; and

a controller comprising hardware, the controller being configured to control a light emission pattern defined by a light emitting region where light is emitted on the light emitting plane,

wherein the controller executes:

first light emission pattern control in which the light emission pattern is changed according to the observation position, or, alternatively,

second light emission pattern control in which the light emission pattern is switched between a plurality of periodic light emission patterns having phases different from each other;

wherein the light emitting region corresponding to each of the plurality of periodic light emission patterns includes a plurality of fringe regions aligned in a first direction at regular intervals,

the controller executes the second light emission pattern control so as to sequentially switch the light emission pattern to the plurality of periodic light emission patterns; and

further comprising a lenticular lens that is disposed between the mounting table and the surface light source and is provided with a plurality of cylindrical lens elements aligned in the first direction at same intervals as the plurality of fringe regions.

7. The observation system according to claim 6 , wherein

conditional expressions

0

<

d

<

P

-

D

·

NA

1

-

N

⁢

A

2

(

44

)

0.5

<

D

F

l

≤

1

(

49

)

are satisfied,

where NA represents a numerical aperture on an object side of the observation optical system, P represents a pitch of the plurality of fringe regions, d represents a width of each of the plurality of fringe regions, D represents an air-converted length of a distance between the light emitting plane and the lenticular lens, and F 1 represents a focal length of the lenticular lens.