Near field optical microscopic examination of a biological specimen

• US 5,286,970 A
• Filed: 01/06/1993
• Issued: 02/15/1994
• Est. Priority Date: 11/19/1990
• Status: Expired due to Term

• Current Assignee: AT&T, Inc.
• Original Assignee: AT&T, Inc.
• Inventors: Trautman, Jay K., Betzig, Robert E., Wolfe, Raymond, Gyorgy, Ernst M.
• Primary Examiner(s): Nelms, David C.
• Assistant Examiner(s): Lee, John R.
• Application Number:
  US08/001,142
• Time in Patent Office: 405 Days
• Field of Search: 250/216, 250/227.11, 250/227.20, 250/227.26, 250/227.28, 250/235, 250/365, 250/368, 250/458.1, 250/459.1, 250/461.1, 250/461.2, 250/467 , 250/492.1, 359/368, 359/385, 359/389, 359/894, 385/12, 385/123, 385/133, 436/164
• US Class Current: 250/227.26
• CPC Class Codes: G01Q 60/22 Probes, their manufacture, or their related instrumentation, e.g. holders
• CPC Class Codes: G11B 2005/001 Controlling recording characteristics of record carriers or transducing characteristics of transducers by means not being part of their structure
• CPC Class Codes: G11B 2005/0021 Thermally assisted recording using an auxiliary energy source for heating the recording layer locally to assist the magnetization reversal
• CPC Class Codes: G11B 27/36 Monitoring, i.e. supervising the progress of recording or reproducing for digital recording G11B20/00 and s.gr.; for monitoring, testing or measuring of TV recorders of the type covered by H04N5/76 and subgroups, see H04N17/06
• CPC Class Codes: G11B 33/10 Indicating arrangements; Warning arrangements G11B15/04, G11B19/04, G11B27/34, G11B27/36 take precedence
• CPC Class Codes: G11B 5/00 Recording by magnetisation or demagnetisation of a record carrier; Reproducing by magnetic means; Record carriers therefor G11B11/00 and G11B13/00 take precedence
• CPC Class Codes: G11B 5/09 Digital recording
• CPC Class Codes: G11B 9/14 using microscopic probe means , i.e. recording or reproducing by means directly associated with the tip of a microscopic electrical probe as used in Scanning Tunneling Microscopy [STM] or Atomic Force Microscopy [AFM] for inducing physical or electrical perturbations in a recording medium; Record carriers or media specially adapted for such transducing of information marking using electrical current B41M5/20; measuring roughness or irregularity of surfaces G01B7/34; details of scanning-probe microscopes G01Q
• CPC Class Codes: G11B 9/1409 Heads
• CPC Class Codes: Y10S 977/853 Biological sample
• CPC Class Codes: Y10S 977/862 Near-field probe

Abstract

An optical system useful, e.g., for near-field scanning optical microscopy is provided. The system incorporates a probe having improved properties. In one embodiment, the probe comprises a tapered and partially metallized portion of a single-mode optical fiber.

Claims

1. A method for examining a biological specimen, comprising the steps of:

impinging incident light on the specimen;

detecting light emitted from a first surface of the specimen at least at one emission wavelength;

constructing a magnified image of a portion of the specimen from the detected light; and

visually examining the magnified image;

wherein the detecting step comprises the steps of;

a) admitting a portion of the emitted light into a waveguiding body through an aperture that is distant from the first surface by no more than the emission wavelength, and that is smaller, in at least one lateral dimension, than the emission wavelength;

b) exciting a guided metallic mode of electromagnetic radiation within the waveguiding body;

c) adiabatically converting a portion of the light within the waveguiding body from the metallic mode to at least one guided dielectric mode; and

d) receiving the adiabatically converted light at a photodetector.

2. The method of claim 1, wherein the specimen has a second surface opposite the first surface, the impinging step comprises impinging light on the second surface, and the light emitted by the first surface is light that has been transmitted through the specimen.

4. The method of claim 1 or 3, wherein the impinging step comprises impinging light on the first surface, and the detecting step comprises detecting reflected light.

5. The method of claim 1 or 3, wherein:

the impinging step comprises impinging, on the first surface, light capable of exciting fluorescence in the specimen; and

the detecting step comprises detecting fluorescent light.

3. A method for examining a biological specimen, comprising the steps of:

impinging incident light on the specimen;

detecting light emitted from a first surface of the specimen at least at one emission wavelength;

constructing a magnified image of a portion of the specimen from the detected light; and

visually examining the magnified image;

wherein the impinging step comprises the steps of;

a) admitting incident light having at least one incident wavelength into an optical waveguiding body such that a guided dielectric mode is excited within the waveguiding body;

b) adiabatically converting a portion of the incident light from the guided dielectric mode to a guided metallic mode; and

c) emitting a portion of the adiabatically converted light from an aperture that is distant from the first surface by no more than the incident wavelength, and that is smaller, in at least one lateral dimension, than the incident wavelength.