Scanning probe microscope using fluorescent light

• US 5,986,256 A
• Filed: 03/11/1998
• Issued: 11/16/1999
• Est. Priority Date: 03/17/1997
• Status: Expired due to Fees

• Current Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Original Assignee: Olympus Optical Company Ltd. (Olympus Corporation)
• Inventors: Yagi, Akira
• Primary Examiner(s): ALLEN, STEPHONE B
• Application Number:
  US09/038,605
• Time in Patent Office: 615 Days
• Field of Search: 250/234, 250/306, 250/458.1, 250/459.1, 250/309
• US Class Current: 250/234
• CPC Class Codes: G01Q 60/42 Functionalisation
• CPC Class Codes: Y10S 977/868 with optical means
• CPC Class Codes: Y10S 977/87 Optical lever arm for reflecting light

Abstract

Disclosed is a scanning probe microscope using fluorescent light, comprising a lever section including a probe, an actuator for moving the probe and a sample relative to each other, a light source unit arranged at a position suitable for permitting at least one of the probe and the sample to be irradiated with light having a first wavelength or a second wavelength, which is emitted from the light source unit, and a detecting unit arranged at a position suitable for optically detecting the positional relationship between the probe and the sample, wherein a first fluorescent material, which emits light having the second wavelength when excited with light of the first wavelength, is imparted to one of the probe and the sample, a second fluorescent material, which emits light having a third wavelength when excited with light having the second wavelength, is imparted to the other of the probe and the sample, and the detecting unit optically detects the positional relationship between the probe and the sample based on the light having the third wavelength.

Claims

1. A scanning probe microscope using fluorescent light, comprising:

a lever section including a probe;

an actuator for moving said probe and a sample relative to each other;

a light source unit arranged at a position suitable for permitting at least one of the probe and the sample to be irradiated with light having a first wavelength or a second wavelength, which is emitted from said light source unit; and

a detecting unit arranged at a position suitable for optically detecting the positional relationship between the probe and the sample,

wherein;

a first fluorescent material, which emits light having the second wavelength when excited with light of said first wavelength, is imparted to one of the probe and the sample;

a second fluorescent material, which emits light having a third wavelength when excited with light having said second wavelength, is imparted to the other of the probe and the sample; and

said detecting unit optically detects the positional relationship between the probe and the sample based on the light having said third wavelength.

2. The scanning probe microscope according to claim 1, wherein said first fluorescent material consists of BFP, and said second fluorescent material consists of GFP.

3. The scanning probe microscope according to claim 1, wherein said first fluorescent material consists of GFP and said second fluorescent material consists of BFP.

4. The scanning probe microscope according to claim 1, wherein said light source unit includes a filter for the excited light, which selectively transmits the light having the first wavelength, and another filter for the excited light, which selectively transmits the light having the second wavelength, any one of these filters being arranged on the optical path of the light emitted from the light source unit.

5. The scanning probe microscope according to claim 1, wherein said light source unit includes a photo chopper for transmitting the light emitted from the light source at a predetermined timing.

6. The scanning probe microscope according to claim 1, wherein said sample is irradiated with light having the second wavelength, which is emitted from said light source unit.

7. The scanning probe microscope according to claim 1, wherein said probe and said sample are positioned deviant from each other in a lateral direction.

8. The scanning probe microscope according to claim 1, wherein said probe and said sample are positioned deviant from each other in a Z-direction.

9. The scanning probe microscope according to claim 1, wherein said probe is irradiated with light of the first wavelength emitted from said light source unit.

10. The scanning probe microscope according to claim 9, wherein said probe is scanned in an XY direction by said actuator, and the light of the first wavelength is controlled to follow the scanning direction of the probe.

11. The scanning probe microscope according to claim 1, further comprising:

an XY scanning circuit for supplying to said actuator a signal for allowing said probe and said sample to be scanned relative to each other;

another detecting unit for detecting the amount of change in the interactive force between the probe and the sample so as to generate an electric signal denoting the amount of change in said force; and

a feedback control unit for generating a control signal based on the output signal of said another detecting unit for driving the actuator so as to control the distance between the probe and the sample.

12. The scanning probe microscope according to claim 11, wherein said another detecting unit includes another light source unit for irradiating said lever section with light emitted therefrom, and a photo-detector for detecting the light reflected from the lever section, the displacement of the lever section based on the change in the interactive force between said probe and said sample being detected by said photo-detector, and an electric signal denoting said displacement being supplied to said feedback control unit.

13. The scanning probe microscope according to claim 12, wherein said interactive force between the probe and the sample is an atomic force or a contact force acting between the probe and the sample.

14. The scanning probe microscope according to claim 1, wherein said first fluorescent material is imparted to said probe to cause the probe to emit light having the second wavelength, and said second fluorescent material is imparted to said sample to cause the sample to emit light having the third wavelength upon excitation with light having the second wavelength.

15. The scanning probe microscope according to claim 14, wherein said detecting unit includes a light detecting element for detecting light having the third wavelength, and an optical filter arranged on an optical path between said light detecting element and the sample and selectively transmitting only the light having the third wavelength.

16. The scanning probe microscope according to claim 15, wherein said detecting unit includes a camera capable of observing said sample and said probe, and a display apparatus for displaying an image based on an electric signal supplied from the camera or based on the light having the third wavelength generated from said light-detecting element.

17. The scanning probe microscope according to claim 16, wherein said detecting unit includes a movable mirror arranged on an optical path between said filter and said light detecting element for transmitting the light of the third wavelength to one of the light detecting element and said camera.

18. The scanning probe microscope according to claim 15, wherein the positional relationship between said probe and said sample is determined on the basis of change in the amount of light of the third wavelength emitted from the sample, said light emission being derived from the energy transfer phenomenon of light.

19. The scanning probe microscope according to claim 16, wherein said light source unit includes a filter for the excited light, which selectively transmits the light having the first wavelength, and another filter for the excited light, which selectively transmits the light having the second wavelength, any one of these filters being arranged on the optical path of the light emitted from the light source unit.

20. The scanning probe microscope according to claim 19, wherein said image display apparatus recognizes the light having the third wavelength, which is emitted from said sample, as information denoting the position of the sample to which is imparted the second fluorescent material, under the condition that the filter for the excited light, which selectively transmits the light having the second wavelength, is arranged on the optical path of the light emitted from the light source unit.

21. The scanning probe microscope according to claim 14, wherein said detecting unit includes:

a light detecting element detecting the light of the second wavelength;

an optical filter arranged between said light detecting element and said sample, said filter selectively transmitting only the light of the second wavelength;

another light detecting element for detecting the light of the third wavelength; and

another optical filter arranged between said another light detecting element and the sample, said another filter selectively transmitting only the light of the third wavelength.

22. The scanning probe microscope according to claim 21, wherein said detecting unit includes a camera capable of observing said sample and said probe, and an image display apparatus for displaying an image based on an output signal of said camera or an image based on the light components of the second wavelength and third wavelength generated from each of said light detecting elements.

23. The scanning probe microscope according to claim 22, wherein said detecting unit includes a movable mirror arranged on an optical path and positioned closer to said sample than said filter and said another filter for transmitting each of the light components having the second wavelength and third wavelength to one of the light detecting element and said camera.

24. The scanning probe microscope according to claim 12, the positional relationship between said probe and said sample is determined on the basis of change in the amounts of the light components having the second wavelength and third wavelength, said change being derived from the energy transfer phenomenon of light.

25. The scanning probe microscope according to claim 22, wherein said light source unit includes a filter for the excited light, which selectively transmits the light having the first wavelength, and another filter for the excited light, which selectively transmits the light having the second wavelength, any one of these filters being arranged on the optical path of the light emitted from the light source unit.

26. The scanning probe microscope according to claim 25, wherein said image display apparatus recognizes the light having the third wavelength, which is emitted from said sample, as information denoting the position of the sample to which is imparted the second fluorescent material, under the condition that the filter for the excited light, which selectively transmits the light having the second wavelength, is arranged on the optical path of the light emitted from the light source unit.

27. The scanning probe microscope according to claim 14, wherein said detecting unit includes a camera capable of observing said sample and said probe, and an image display apparatus for displaying an image based on the output signal from said camera.

28. The scanning probe microscope according to claim 14, wherein said first fluorescent material is imparted to said probe by an LB film forming method or imparted to a latex ball attached to the tip of the probe, and said second fluorescent material is what is used for staining the sample by gene manipulation.

29. The scanning probe microscope according to claim 1, wherein said first fluorescent material is imparted to said probe to allow the probe to emit light having the second wavelength, said second fluorescent material is imparted to said sample to allow the sample to emit light having the third wavelength, and said detecting unit includes a light detecting element for detecting the light having the third wavelength.

30. The scanning probe microscope according to claim 29, further comprising:

an XY scanning circuit for supplying to said actuator a signal for allowing said probe and said sample to be scanned relative to each other;

another detecting unit for detecting the amount of change in the interactive force between the probe and the sample so as to generate an electric signal denoting the amount of change in said force; and

a feedback control unit for generating a control signal based on the output signal of said another detecting unit for driving the actuator so as to control the distance between the probe and the sample, the light having the third wavelength being detected by said light detecting element while the distance between the probe and the sample is being controlled by said feedback control unit.

31. The scanning probe microscope according to claim 30, wherein said feedback control unit to serving to drive said actuator, to permit maintaining constant the distance between said probe and said sample.

32. The scanning probe microscope according to claim 30, wherein said feedback control unit drives said actuator to move said probe toward said sample so as to be pushed into the sample, the pushing amount of the probe into the sample being detected by said another detecting unit and supplied to said feedback control unit.

33. The scanning probe microscope according to claim 30, further comprising exciting means for vibrating said probe, and said feedback control unit to serving to drive said actuator, to control the distance between the probe and the sample to maintain constant the amplitude of the vibrating probe.

34. The scanning probe microscope according to claim 33, wherein said exciting means consists of a function generator supplying an excitation modulation signal to said actuator.

35. The scanning probe microscope according to claim 33, further comprising take-in means for taking in the light having the third wavelength which is emitted in synchronism with vibration of the probe.

36. The scanning probe microscope according to claim 35, wherein said take-in means consists of a lock-in-amplifier.

37. The scanning probe microscope according to claim 1, wherein said first fluorescent material is imparted to said sample to cause the sample to emit light having the second wavelength, and said second fluorescent material is imparted to said probe to cause the probe to emit light having the third wavelength upon excitation with light having the second wavelength.

38. The scanning probe microscope according to claim 37, wherein said detecting unit includes a camera capable of observing said sample and said probe and an image display apparatus for displaying an image based on the output signal of said camera.

39. The scanning probe microscope according to claim 37, wherein said first fluorescent material is imparted to said probe by an LB film forming method or imparted to a latex ball attached to the tip of the probe, and said second fluorescent material is what is used for staining the sample by gene manipulation.

40. The scanning probe microscope according to claim 37, further comprising:

an XY scanning circuit for supplying to said actuator a signal for allowing said probe and said sample to be scanned relative to each other;

another detecting unit for detecting the amount of change in the interactive force between the probe and the sample so as to generate an electric signal denoting the amount of change in said force; and

a feedback control unit for generating a control signal based on the output signal of said another detecting unit for driving the actuator so as to control the distance between the probe and the sample,

wherein said feedback control unit drives said actuator to move said probe toward said sample so as to be pushed into the sample, the pushing amount of the probe into the sample being detected by said another detecting unit and supplied to said feedback control unit.

41. The scanning probe microscope according to claim 37, wherein said detecting unit includes:

a light detecting element for detecting light of the second wavelength;

an optical filter arranged between said light detecting element and said sample and selectively transmitting only the light of the second wavelength;

another light detecting element for detecting light of the third wavelength; and

another optical filter arranged between said another light detecting element and the sample and selectively transmitting only the light of the third wavelength.

42. The scanning probe microscope according to claim 41, wherein said detecting unit includes a camera capable of observing said sample and said probe, and an image display apparatus for displaying an image based on the output signal from said camera or based on the light components of the second and third wavelengths supplied from each of said light detecting elements.

43. The scanning probe microscope according to claim 41, wherein the positional relationship between said probe and said sample is determined on the basis of the changes in the amounts of light components having the second and third wavelengths, said changes being derived from the energy transfer phenomenon of light.

44. A scanning probe microscope using fluorescent light, comprising:

a probe acting as a provisional light source for supplying a light component to a sample;

a light source unit for supplying light to said probe to permit the probe to act as a provisional light source for supplying light to said sample;

an actuator for moving the probe and the sample relative to each other; and

a detecting unit mounted at a position suitable for optically detecting the positional relationship between the probe and the sample,

wherein a fluorescent material is imparted to the sample by means of gene manipulation, said fluorescent material is excited by a light component emitted from the probe so as to emit light, and the light thus emitted is detected by said detecting unit.

45. A scanning probe microscope using fluorescent light, comprising:

a lever section including a probe;

an actuator for moving said probe and a sample relative to each other;

a light source means arranged at a position suitable for permitting at least one of the probe and the sample to be irradiated with light having a first wavelength or a second wavelength, which is emitted from said light source means; and

a detecting means arranged at a position suitable for optically detecting the positional relationship between the probe and the sample,

wherein;

a first fluorescent material, which emits light having the second wavelength when excited with light of said first wavelength, is imparted to one of the probe and the sample;

a second fluorescent material, which emits light having a third wavelength when excited with light having said second wavelength, is imparted to the other of the probe and the sample; and

said detecting means optically detects the positional relationship between the probe and the sample based on the light having said third wavelength.