Optical microscope and method for detecting lens immersion

Patent metadata

Field	Value
Publication number	US-9977231-B2
Application number	US-201715430975-A
Country	US
Kind code	B2
Filing date	Feb 13, 2017
Priority date	Jun 30, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

An optical microscope and method for detecting lens immersion in optical microscopy includes an ultrasound circuit acoustically coupled to both an objective lens and a sample of an optical microscope, the ultrasound circuit comprising an ultrasound transmitter and an ultrasound receiver. The optical microscope and method includes transmitting an ultrasound pulse from the ultrasound transmitter to the ultrasound receiver, determining that a transit time of the ultrasound pulse is less than a threshold time, and providing an output signal from the pulse discriminator indicating that the ultrasound pulse is less than the threshold time.

First claim

I claim:

1. A method for determining lens immersion in an instrument, the method comprising:
acoustically coupling an ultrasound circuit to both a lens and a sample of the instrument, the ultrasound circuit comprising an ultrasound transmitter and an ultrasound receiver;
configuring the ultrasound circuit to provide a first acoustic path, through a body of the instrument, when the lens and the sample are not both in direct contact with an immersion fluid of the instrument, and a second, shorter, acoustic path through the immersion fluid, when the lens and the sample are both in direct contact with the immersion fluid;
transmitting an ultrasound pulse from the ultrasound transmitter to the ultrasound receiver;
measuring a transit time of the ultrasound pulse;
if the transit time is not less than a threshold time, determining that the ultrasound pulse was transmitted along the first acoustic path; and
if the transit time is less than the threshold time, determining that the ultrasound pulse was transmitted along the second acoustic path.

2. The method of claim 1 , further comprising providing an adjustment mechanism able to control a distance between the lens and the sample, and controlling the adjustment mechanism based on the measured transit time of the ultrasound pulse.

3. The method of claim 2 , wherein said controlling the adjustment mechanism further comprises controlling the adjustment mechanism to automatically adjust the distance between the lens and the sample.

4. The method of claim 2 , wherein said controlling the adjustment mechanism further comprises controlling the adjustment mechanism to automatically decrease the distance between the lens and the sample a preset distance after determining that the transit time is greater than the threshold time.

5. The method of claim 2 , wherein said controlling the adjustment mechanism further comprises controlling the adjustment mechanism to automatically decrease the distance between the lens and the sample until the transit time is less than the threshold time.

6. The method of claim 1 , further comprising providing, from a pulse discriminator, an output signal indicating that the transit time of the ultrasound pulse is less than the threshold time, wherein the output signal further indicates that the lens and the sample are both in direct contact with the immersion fluid.

7. The method of claim 6 , further comprising providing a status confirmation in response to the output signal confirming that the lens and the sample are both in direct contact with the immersion fluid.

8. The method of claim 1 , wherein the threshold time is between 15 μS and 25 μS.

9. A method for controlling lens immersion in an instrument, the method comprising:
acoustically coupling an ultrasound circuit to both a lens and a sample of the instrument, the ultrasound circuit comprising an ultrasound transmitter and an ultrasound receiver;
transmitting an ultrasound pulse from the ultrasound transmitter to the ultrasound receiver wherein the ultrasound pulse travels through an immersion fluid in contact with both the lens and the sample;
measuring an amplitude of the ultrasound pulse;
providing an adjustment mechanism able to control a distance between the lens and the sample; and
if the measured amplitude is greater than a threshold amplitude, controlling the adjustment mechanism to adjust the distance between the lens and the sample based on the measured amplitude of the ultrasound pulse.

10. The method of claim 9 , further comprising controlling the adjustment mechanism to automatically adjust the distance between the lens and the sample based on the measured amplitude of the ultrasound pulse.

11. The method of claim 10 , wherein said controlling the adjustment mechanism further comprises controlling the adjustment mechanism to automatically increase the distance between the lens and the sample a preset distance after determining that the measured amplitude is greater than the threshold amplitude.

12. The method of claim 10 , wherein said controlling the adjustment mechanism further comprises controlling the adjustment mechanism to automatically increase the distance between the lens and the sample slide until the measured amplitude is less than the threshold amplitude.

13. The method of claim 9 , further comprising providing an output signal to indicate that the amplitude for the ultrasound pulse is greater than the threshold amplitude.

14. A method for automatically focusing an instrument, the method comprising:
acoustically coupling an ultrasound circuit to both a lens and a sample of the instrument, the ultrasound circuit comprising an ultrasound transmitter and an ultrasound receiver,
transmitting an ultrasound pulse from the ultrasound transmitter to the ultrasound receiver, wherein the ultrasound pulse travels through an immersion fluid in contact with both the lens and the sample;
determining a distance between the lens and the sample based on the ultrasound pulse;
providing an adjustment mechanism able to control a distance between the lens and the sample; and
if the determined distance between the lens and the sample is different than a threshold distance, controlling the adjustment mechanism to automatically adjust the distance between the lens and the sample and enable automatic focusing of the lens with respect to the sample.

15. The method of claim 14 , wherein the instrument is an optical microscope and the lens is an objective lens.

16. The method of claim 14 , wherein the ultrasound pulse comprises a single frequency pulse or a spectral pulse comprising a spectrum of different frequencies.

17. The method of claim 16 , wherein the ultrasound pulse comprises a single frequency pulse, and wherein determining the distance between the lens and the sample further comprises measuring a decay of the ultrasound pulse as the ultrasound pulse travels through the immersion fluid.

18. The method of claim 16 , wherein the ultrasound pulse comprises a spectral pulse, and wherein determining the distance between the lens and the sample further comprises measuring an attenuation of frequencies in the spectral pulse as the spectral pulse travels through the immersion fluid.

19. An instrument comprising:
a lens;
a holder configured to receive a sample;
an immersion fluid deposited on at least one of the lens and the sample;
an ultrasound circuit acoustically coupled to the lens and the sample in the holder, the ultrasound circuit comprising an ultrasound transmitter and an ultrasound receiver, wherein the ultrasound circuit is configured to provide a first acoustic path when the lens and the sample are not both in direct contact with the immersion fluid, and a second, shorter, acoustic path through the immersion fluid, when the lens and the sample are in direct contact with the immersion fluid; and
an adjustment mechanism configured to control a distance between the lens and the sample.

20. The instrument of claim 19 , further comprises a pulse discriminator electrically coupled to the ultrasound circuit, wherein the pulse discriminator is configured to determine that, if a measured transit time of the ultrasound pulse is greater than a threshold time, the ultrasound pulse was transmitted along the first acoustic path; and that if the measured transit time is less than the threshold time, the ultrasound pulse was transmitted along the second acoustic path.

21. The instrument of claim 19 , wherein the adjustment mechanism is configured to automatically de

Assignees

• Gen Electric

Inventors

• Dougherty William Michael

Classifications

• G02B21/247 Primary

  Differential detectors · CPC title

• G01N29/4427

  with stored values, e.g. threshold values · CPC title

• G02B21/34

  Microscope slides, e.g. mounting specimens on microscope slides · CPC title

• G02B21/02

  Objectives · CPC title

• G02B21/33

  Immersion oils {, or microscope systems or objectives for use with immersion fluids} · CPC title