Methods and apparatus for electrostatic control of expelled material for lens cleaners

Patent metadata

Field	Value
Publication number	US-11607704-B2
Application number	US-201715492395-A
Country	US
Kind code	B2
Filing date	Apr 20, 2017
Priority date	Apr 20, 2017
Publication date	Mar 21, 2023
Grant date	Mar 21, 2023

Abstract

Methods and apparatus for electrostatic control of expelled material for lens cleaners are disclosed. In certain described examples, an apparatus can expel fluid by atomization from a central area of the surface using an ultrasonic transducer mechanically coupled to the surface. A first electrode can be arranged relative to the central area of the surface. A second electrode can be located in a peripheral area relative to the central area of the surface, in which a voltage can be applied between the first and second electrodes to attract atomized fluid at the peripheral area.

First claim

What is claimed is:

1. An apparatus comprising:
an optical surface;
an ultrasonic transducer mechanically coupled to the optical surface, the ultrasonic transducer having an input, and the ultrasonic transducer configured to atomize a fluid on the optical surface by vibrating the optical surface responsive to a signal received at the input;
a first signal generator having an output coupled to the input;
a first electrode having a first surface facing the optical surface; and
a second electrode having a second surface in a peripheral area outside the optical surface, wherein the second surface is angled relative to the optical surface, and the second electrode is configured to move the atomized fluid away from the optical surface by generating an electric field between the first and second electrodes; and
a second signal generator coupled between the first and second electrodes.

2. The apparatus of claim 1 , wherein the optical surface is hydrophobic.

3. The apparatus of claim 1 , wherein the peripheral area is hydrophobic.

4. The apparatus of claim 1 , wherein the optical surface is at least partially enclosed by the peripheral area.

5. The apparatus of claim 1 , wherein an angle between the optical surface and the second electrode is a right angle.

6. The apparatus of claim 1 , wherein an angle between the optical surface and the second electrode is an obtuse angle.

7. The apparatus of claim 1 , wherein an angle between the optical surface and the second electrode is an acute angle.

8. The apparatus of claim 1 , wherein the signal is a first signal;
wherein the first signal generator is configured to generate the first signal having a first frequency and a second signal having a second frequency; and
wherein the ultrasonic transducer has first and second resonant frequency bands, the first frequency is within the first resonant frequency band, and the second frequency is within the second resonant frequency band.

9. The apparatus of claim 8 , wherein the ultrasonic transducer is configured to reduce a droplet of the fluid from a first size to a second size by vibrating the optical surface at the first frequency responsive to the first signal, and to reduce the droplet from the second size to a third size by vibrating the optical surface at the second frequency responsive to the second signal.

10. The apparatus of claim 9 , wherein the first frequency is higher than the second frequency.

11. The apparatus of claim 1 , wherein the first surface of the first electrode is attached onto the optical surface.

12. The apparatus of claim 11 , wherein the first electrode comprises an electrode coating on the optical surface.

13. The apparatus of claim 1 , wherein the first surface forms an angle with the second surface.

14. The apparatus of claim 1 , wherein the second electrode is configured to attract the atomized fluid away from the optical surface towards the peripheral area, by using the electric field to electrostatically control the atomized fluid responsive to a voltage between the first and second electrodes provided by the second signal generator, in which the first electrode is configured to receive a first polarity of the voltage, the second electrode is configured to receive a second polarity of the voltage, and the second polarity is opposite the first polarity.

15. The apparatus of claim 14 , wherein the first polarity is a positive polarity, and the second polarity is a negative polarity.

16. The apparatus of claim 1 , wherein the second signal generator includes a voltage generator.

17. An apparatus comprising:
an optical surface that is hydrophobic;
an ultrasonic transducer mechanically coupled to the optical surface, the ultrasonic transducer having an input, and the ultrasonic transducer configured to atomize a fluid on the optical surface by vibrating the optical surface responsive to a signal received at the input;
a first signal generator having an output coupled to the input;
a first electrode having a first surface facing the optical surface;
a second electrode having a second surface in a peripheral area that at least partially encloses the optical surface, wherein an angle between the optical surface and the second surface is a right angle, an obtuse angle or an acute angle, and the second electrode is configured to move the atomized fluid away from the optical surface by generating an electric field between the first and second electrodes; and
a second signal generator coupled between the first and second electrodes.

18. The apparatus of claim 17 , wherein the peripheral area is hydrophobic.

19. The apparatus of claim 17 , wherein the signal is a first signal;
wherein the first signal generator is configured to generate the first signal having a first frequency and a second signal having a second frequency; and
wherein the ultrasonic transducer has first and second resonant frequency bands, the first frequency is within the first resonant frequency band, and the second frequency is within the second resonant frequency band.

20. The apparatus of claim 19 , wherein the ultrasonic transducer is configured to reduce a droplet of the fluid from a first size to a second size by vibrating the optical surface at the first frequency responsive to the first signal, and to reduce the droplet from the second size to a third size by vibrating the optical surface at the second frequency responsive to the second signal.

21. The apparatus of claim 20 , wherein the first frequency is higher than the second frequency.

22. The apparatus of claim 17 , wherein the second electrode is configured to attract the atomized fluid from the optical surface towards the peripheral area, by using the electric field to electrostatically control the atomized fluid responsive to a voltage between the first and second electrodes provided by the second signal generator, in which the first electrode is configured to receive a first polarity of the voltage, the second electrode is configured to receive a second polarity of the voltage, and the second polarity is opposite the first polarity.

23. The apparatus of claim 22 , wherein the first polarity is a positive polarity, and the second polarity is a negative polarity.

Assignees

• Texas Instruments Inc

Inventors

• Cook Benjamin Stassen
• Revier Daniel Lee
• Fedigan Stephen John
• Magee David Patrick

Classifications

• B05B17/0669 Primary

  Excitation frequencies · CPC title

• B05B17/0661

  Transducer materials · CPC title

• G02B1/18

  Coatings for keeping optical surfaces clean, e.g. hydrophobic or photo-catalytic films (G02B1/16 takes precedence) · CPC title

• G02B27/0006

  with means to keep optical surfaces clean, e.g. by preventing or removing dirt, stains, contamination, condensation (G02B1/18 takes precedence; cleaning in general B08B) · CPC title

• B05B5/087

  Arrangements of electrodes, e.g. of charging, shielding, collecting electrodes (B05B5/12, B05B5/14 take precedence; arrangements of electrodes on the discharge apparatus B05B5/0533) · CPC title