Method and An Imaging System for Holographic Imaging

• US 20190310584A1
• Filed: 12/08/2017
• Published: 10/10/2019
• Est. Priority Date: 12/09/2016
• Status: Active Grant

• Current Assignee: IMEC International
• Original Assignee: IMEC International
• Inventors: Lin, Ziduo, Yurt, Abdulkadir, Stahl, Richard, Vanmeerbeeck, Geert
• Granted Patent: US 11,175,625 B2
• Time in Patent Office: Days
• CPC Class Codes: G03H 1/0005 Adaptation of holography to specific applications holographic optical element G02B5/32; holographic scanner G02B26/106; recognition using holographic mask G06V10/88; holographic memories G11B7/0065, G11C13/042
• CPC Class Codes: G03H 1/0443 Digital holography, i.e. recording holograms with digital recording means holobject computation G03H1/0866
• CPC Class Codes: G03H 1/0465 Particular recording light; Beam shape or geometry G03H1/06 takes precedence
• CPC Class Codes: G03H 1/0486 Improving or monitoring the quality of the record, e.g. by compensating distortions, aberrations
• CPC Class Codes: G03H 2001/005 in microscopy, e.g. digital holographic microscope [DHM] microscopes G02B21/00; digital holography G03H1/0866
• CPC Class Codes: G03H 2001/0212 Light sources or light beam properties G03H1/06, G03H1/24 take precedence; corresponding details, see subgroups of G03H2222/00
• CPC Class Codes: G03H 2001/0447 In-line recording arrangement
• CPC Class Codes: G03H 2001/0471 Object light being transmitted through the object, e.g. illumination through living cells
• CPC Class Codes: G03H 2001/0491 by monitoring the hologram formation, e.g. via a feed-back loop
• CPC Class Codes: G03H 2222/12 Single or narrow bandwidth source, e.g. laser, light emitting diode [LED]
• CPC Class Codes: G03H 2222/20 Coherence of the light source
• CPC Class Codes: G03H 2226/11 Electro-optic recording means, e.g. CCD, pyroelectric sensors

Abstract

Example embodiments relate to methods and imaging systems for holographic imaging. One embodiment includes a method for holographic imaging of an object. The method includes driving a laser using a current which is below a threshold current of the laser. The method also includes illuminating the object using illumination light output by the laser. Further, the method includes detecting an interference pattern formed by object light, having interacted with the object, and reference light of the illumination light.

Claims

1. A method for holographic imaging of an object, comprising:

driving a laser using a current which is below a threshold current of the laser;

illuminating the object using illumination light output by the laser; and

detecting an interference pattern formed by object light, having interacted with the object, and reference light of the illumination light.

2. The method according to claim 1, further comprising reconstructing an optical image of the object based on the detected interference pattern.

3. The method according to claim 1, further comprising controlling driver circuitry to control the current driving the laser.

4. The method according to claim 3, further comprising:

identifying undesired interference fringes in the detected interference pattern; and

in response to identifying the undesired interference fringes;

controlling the driver circuitry to decrease the current driving the laser; and

detecting a second interference pattern based on the illumination light output by the laser driven using a decreased current.

5. The method according to claim 3, wherein controlling the driver circuitry is based on an ambient temperature to the laser.

6. The method according to claim 1, wherein the object is imaged by in-line holographic imaging.

7. The method according to claim 1, wherein the method is performed as part of a holographic microscopy study.

8. An imaging system for holographic imaging, comprising:

a laser source arranged to output illumination light towards an object;

an image sensor comprising light-detecting elements arranged to detect an interference pattern formed by object light, having interacted with the object, and reference light of the illumination light; and

a controller arranged to control a current driving the laser source to maintain the current below a threshold current of the laser source.

9. The imaging system according to claim 8, wherein the controller is further arranged to control the image sensor to detect the interference pattern.

10. The imaging system according to claim 8, further comprising a processing unit arranged to receive the interference pattern from the image sensor and to reconstruct an optical image of the object based on the interference pattern.

11. The imaging system according to claim 8, wherein the laser source is a laser diode.

12. The imaging system according to claim 8, wherein the controller is further arranged to receive an indication based on undesired interference fringes being identified in the detected interference pattern, and wherein the controller is further arranged to decrease the current driving the laser source based on the received indication.

13. The imaging system according to claim 8, wherein the controller is further arranged to control the current driving the laser source based on an ambient temperature to the laser source.

14. A measurement instrument comprising an imaging system,

wherein the imaging system comprises:

a laser source arranged to output illumination light towards an object;

an image sensor comprising light-detecting elements arranged to detect an interference pattern formed by object light, having interacted with the object, and reference light of the illumination light; and

a controller arranged to control a current driving the laser source to maintain the current below a threshold current of the laser source, and

wherein the measurement instrument is arranged to determine a measure of the object based on processing the detected interference pattern.

15. The measurement instrument according to claim 14, wherein the object is a body fluid sample.

16. The measurement instrument according to claim 14, wherein the controller is further arranged to control the image sensor to detect the interference pattern.

17. The measurement instrument according to claim 14, further comprising a processing unit arranged to receive the interference pattern from the image sensor and to reconstruct an optical image of the object based on the interference pattern.

18. The measurement instrument according to claim 14, wherein the laser source is a laser diode.

19. The measurement instrument according to claim 14, wherein the controller is further arranged to receive an indication based on undesired interference fringes being identified in the detected interference pattern, and wherein the controller is further arranged to decrease the current driving the laser source based on the received indication.

20. The measurement instrument according to claim 14, wherein the controller is further arranged to control the current driving the laser source based on an ambient temperature to the laser source.