Systems, devices, and methods for automatic microscopic focus
An automatic focus system for an optical microscope that facilitates faster focusing by using at least two cameras. The first camera can be positioned in a first image forming conjugate plane and receives light from a first illumination source that transmits light in a first wavelength range. The second camera can be positioned at an offset distance from the first image forming conjugate plane and receives light from a second illumination source that transmits light in a second wavelength range.
1. A system for automatically focusing a microscope, comprising:
a first image sensor, configured for focusing, positioned on an image forming conjugate plane;
a second image sensor, configured for focusing, positioned at an offset distance from the image forming conjugate plane; and
a hardware processor coupled to the first image sensor and the second image sensor that is configured to:
determine, using the first image sensor, when a specimen is in focus;
determine, using the second image sensor, a sharpness setpoint for the specimen when the specimen is determined to be in focus for the first image sensor;
after movement of the specimen, determine, using the second image sensor, a first sharpness value of the specimen;
perform at least one of: determine whether the first sharpness value of the specimen is higher than the sharpness setpoint; and determine whether the first sharpness value of the specimen is lower than the sharpness setpoint; and
adjust the microscope so that a second sharpness value of the specimen determined using the second image sensor corresponds to the sharpness setpoint.
2. The system of claim 1 , wherein the hardware processor is further configured to:
determine a sharpness curve for the specimen using the second image sensor; and
adjust the microscope based on the sharpness curve so that the second sharpness value of the specimen determined using the second image sensor corresponds to the sharpness setpoint.
3. The system of claim 1 , further comprising:
a first filter positioned in a first optical path between a second illumination source and the first image sensor to prevent light from the second illumination source from reaching the first image sensor; and
a second filter positioned in a second optical path between a first illumination source and the second image sensor to prevent light from the first illumination source from reaching the second image sensor.
4. The system of claim 1 , wherein the first image sensor is also configured for taking images of the specimen when the specimen is determined to be in focus.
5. The system of claim 1 , further comprising a field diaphragm positioned in an optical path between a primary illumination source and an objective.
6. The system of claim 1 , wherein the hardware processor is further configured adjust the microscope to achieve a coarse focus and a fine focus.
7. The system of claim 1 , wherein adjusting the microscope so that the second sharpness value of the specimen determined using the second image sensor corresponds to the sharpness setpoint comprises repeatedly:
adjusting the microscope;
determining the second sharpness value using the second image sensor; and
comparing the second sharpness value to the sharpness setpoint.
8. The system of claim 1 , wherein the hardware processor is further configured to save an adjustment setting of the microscope.
9. The system of claim 8 , wherein the saved adjustment setting is used to determine a position of the second image sensor relative to the second image forming conjugate plane.
10. A system for automatically focusing a microscope, comprising:
a first image sensor, configured for taking images of a specimen when the specimen is determined to be in focus, positioned on an image forming conjugate plane;
a second image sensor, configured for focusing, positioned on a second image forming conjugate plane;
a third image sensor, configured for focusing, positioned at an offset distance from the second image forming conjugate plane; and
a hardware processor coupled to the second image sensor and the third image sensor that is configured to:
determine, using the second image sensor, when the specimen is in focus;
determine, using the third image sensor, a sharpness setpoint for the specimen when the specimen is determined to be in focus for the second image sensor;
after movement of the specimen, determine, using the third image sensor, a first sharpness value of the specimen;
perform at least one of: determine whether the first sharpness value of the specimen is higher than the sharpness setpoint; and determine whether the first sharpness value of the specimen is lower than the sharpness setpoint; and
adjust the microscope so that a second sharpness value of the specimen determined using the third image sensor corresponds to the sharpness setpoint.
11. The system of claim 10 , wherein the hardware processor is further configured to:
determine a sharpness curve for the specimen using the third image sensor; and
adjust the microscope based on the sharpness curve so that the second sharpness value of the specimen determined using the third image sensor corresponds to the sharpness setpoint.
12. The system of claim 10 , further comprising:
a first filter positioned in a first optical path between a second illumination source and the first image sensor to prevent light from the second illumination source from reaching the first image sensor; and
a second filter positioned in a second optical path between a first illumination source and the second and third image sensors to prevent light from the first illumination source from reaching the second and third image sensors.
13. The system of claim 10 , further comprising a field diaphragm positioned in an optical path between a first illumination source and an objective.
14. The system of claim 10 , wherein the hardware processor is further configured to adjust the microscope to achieve a coarse focus and a fine focus.
15. The system of claim 10 , wherein adjusting the microscope so that the second sharpness value of the specimen determined using the third image sensor corresponds to the sharpness setpoint comprises repeatedly:
adjusting the microscope;
determining the second sharpness value using the third image sensor; and
comparing the second sharpness value to the sharpness setpoint.
16. The system of claim 10 , wherein the hardware processor is configured to save an adjustment setting of the microscope.
17. The system of claim 16 , wherein the saved adjustment setting is used to determine a position of the third image sensor relative to the third image forming conjugate plane.