Selective plane illumination microscopy instruments

1. An optical arrangement providing selective plane illumination, comprising an inverted illumination objective mounted below a sample support and arranged to provide a line or plane of light propagating at the sample support, and at least one image collection objective mounted above the sample support, the inverted illumination objective having an illumination objective optical axis, and the image collection objective having an image collection objective optical axis, wherein the illumination light is arranged to propagate the illumination objective laterally offset to the illumination objective optical axis such that the illumination light leaving the illumination objective propagates toward the sample support at an oblique angle relative to the illumination objective optical axis, and wherein the image collection objective optical axis has an angle −α which is obtuse to the illumination objective optical axis and generally perpendicular to light propagating at the sample support,

wherein the at least one image collection objective comprises first and second image collection objectives each mounted on opposing sides of the illumination objective optical axis and wherein, the illumination light is arranged to propagate on alternate opposing sides of the illumination objective optical axis along respective first and second paths, to provide the light propagating at the sample support to the first or the second image collection objective alternately.

2. The optical arrangement of claim 1 , wherein the angle α is between 100 and 170 degrees.

3. The optical arrangement of claim 1 , wherein the optical arrangement further comprises an optical manipulators to provide the illumination light in the form of a line, a plane or a sheet of a collimated light.

4. A method of illuminating a sample to provide selective plane illumination microscopy (SPIM), the method comprising:

providing the optical arrangement of claim 1 ;

causing the illumination light to propagate on alternate opposing sides of the illumination objective optical axis along respective first and second paths;

providing the light propagating at the sample support to the first or the second image collection objective alternately;

capturing one or more images collected by the first and second image collection objectives; and

formulating a structured image from the images captured by both image collection objectives.

5. A selective plane illumination microscopy (SPIM) instrument comprising the optical arrangement of claim 1 .

6. The instrument of claim 5 , adaptable to perform also one or both of structured illumination microscopy (SIM) and total internal reflection fluorescence (TIRF) microscopy techniques.

7. The instrument of claim 5 , wherein there is a space between the illumination objective and the sample support, and the space is bridged by a liquid.

8. The instrument of claim 5 , wherein the sample support is moveable in a direction perpendicular to the illumination objective optical axis.

9. The instrument of claim 8 , wherein the sample support is moveable in the direction perpendicular to the illumination objective optical axis in a continuous motion.

10. The optical arrangement of claim 1 , wherein the angle α is between 125 and 145 degrees.

11. The optical arrangement of claim 1 , wherein the angle α is 135 degree.

12. The optical arrangement of claim 1 , wherein the illumination light is a coherent light.

13. The optical arrangement of claim 1 , wherein the illumination light is a laser light.