Imaging flow cytometer

1. An imaging flow cytometer, comprising:

at least one flow channel configured to permit an observation target to flow therethrough, which observation target comprises a plurality of cross-sections, wherein at least one cross-section of the plurality of cross-sections comprises at least one optically detectable moiety;

a light source in optical communication with the flow channel, wherein the light source is configured to irradiate the at least one flow channel with an excitation light that is sufficient to induce the at least one optically detectable moiety to emit at least one optically detectable signal, wherein the excitation light is configured to spread in a form of a sheet having a width wider than a diameter of the observation target in a first axis direction and a thickness thinner than the observation target in a direction orthogonal to the first axis direction;

an imaging element comprising at least one pixel configured to detect the at least one optically detectable signal emitted by the observation target upon exposure to the excitation light; and

a computer configured to (i) use the at least one optically detectable signal to generate a plurality of cross-sectional images of the observation target, and (ii)

use the plurality of cross-sectional images to generate a three-dimensional (3D) image of the observation target.

2. The imaging flow cytometer according to claim 1 , wherein the observation target is sorted from one or more objects on the basis of the 3D image or one or more cross-sectional images of the plurality of cross-sectional images.

3. The imaging flow cytometer according to claim 1 , wherein the at least one flow channel comprises a plurality of flow channels.

4. The imaging flow cytometer according to claim 1 , further comprising a light modulation unit disposed on a light path between the light source and the imaging element.

5. The imaging flow cytometer according to claim 4 , wherein the light modulation unit is configured to change an optical characteristic of at least one of the excitation light to the flow channel and the optically detectable signal emitted by the observation target.

6. The imaging flow cytometer according to claim 1 , wherein the observation target comprises a cell.

7. The imaging flow cytometer according to claim 1 , wherein the sheet-like excitation light comprises coherent light.

8. The imaging flow cytometer according to claim 1 , wherein the sheet-like excitation light comprises narrowed coherent light.

9. The imaging flow cytometer according to claim 1 , further comprising an objective lens configured to receive and direct the sheet-like excitation light to the flow channel.

10. The imaging flow cytometer according to claim 9 , wherein the objective lens is configured to focus the sheet-like excitation light on a cross-section of the plurality of cross-sections.

11. The imaging flow cytometer according to claim 1 , wherein the imaging element comprises one or more members selected from the group consisting of: single-pixel detector, line scan camera, and complementary metal oxide semiconductor (sCMOS) camera.

12. The imaging flow cytometer according to claim 3 , wherein the plurality of flow channels are arranged in parallel.

13. The imaging flow cytometer according to claim 3 , wherein the imaging element is configured to obtain the plurality of cross-sectional images through each flow channel of the plurality of flow channels.

14. The imaging flow cytometer according to claim 4 , wherein the light modulation unit comprises a plurality of regions having different optical characteristics.

15. The imaging flow cytometer according to claim 14 , wherein the different optical characteristics comprise one or more members selected from the group consisting of: light transmittance, light intensity, light wavelength, and light polarization.

16. The imaging flow cytometer according to claim 1 , wherein the excitation light comprises fluorescence excitation light, wherein the at least one optically detectable signal comprises at least one fluorescence signal.

17. A method, comprising:

(a) permitting an observation target to flow through at least one flow channel, which observation target comprises a plurality of cross-sections, wherein at least one cross-section of the plurality of cross-sections comprises at least one optically detectable moiety;

(b) irradiating the at least one flow channel with an excitation light that is sufficient to induce the at least one optically detectable moiety to emit at least one optically detectable signal, wherein the excitation light spreads in a form of a sheet having a width wider than a diameter of the observation target in a first axis direction and a thickness thinner than the observation target in a direction orthogonal to the first axis direction;

(c) detecting the at least one optically detectable signal emitted by the observation target upon exposure to the excitation light;

(d) using the at least one optically detectable signal to generate a plurality of cross-sectional images of the observation target; and

(e) using the plurality of cross-sectional images to generate a three-dimensional (3D) image of the observation target.

18. The imaging flow cytometer according to claim 1 , wherein the at least one pixel of the imaging element is configured to acquire only an intensity of the at least one optically detectable signal emitted by the observation target.

19. The imaging flow cytometer according to claim 1 , wherein the excitation light is a structured light.

20. The imaging flow cytometer according to claim 1 , wherein the excitation light is formed in a sheet shape by narrowing coherent light.