CN-119757297-B - Optical system and method for illuminating a sample plane

Abstract

Various embodiments may provide a method of illuminating a sample plane. The method may include providing an illumination subsystem including a light source and at least one lens, the illumination subsystem having an original optical axis with an angle of incidence greater than 0 ° and less than 90 ° from a normal to a sample plane. A reference illumination profile is generated on the sample using the illumination subsystem at the primary tilt position. The method may further comprise rotating the illumination subsystem about a pivot point between the light source and the sample plane along the original optical axis to a secondary tilt position having another optical axis such that the symmetry of the intensity distribution is improved in the case that the adjusted illumination distribution produced by the illumination subsystem at the sample plane is compared to a reference illumination distribution produced at the sample plane by the illumination subsystem located at the original optical axis.

Inventors

• Ronnie Shaw
• WEI XIAOYANG
• Hong Rusong

Assignees

• 高科技器械私人有限公司
• 康比纳提公司

Dates

Publication Date

20260512

Application Date

20190719

Claims (20)

1. 1. A method of illuminating a sample plane, the method comprising: Providing an illumination subsystem comprising a light source and at least one lens, the illumination subsystem having an original optical axis at a first angle of incidence of greater than 0 ° and less than 90 ° from a normal to the sample plane; Generating a reference illumination profile on the sample plane by the illumination subsystem at a primary tilt position, an Rotating the illumination subsystem about a pivot point to a secondary tilt position having another optical axis until symmetry of an intensity distribution is improved in a case where an adjusted illumination distribution produced by the illumination subsystem at the sample plane is compared to the reference illumination distribution produced by the illumination subsystem at the sample plane at the original optical axis, wherein the pivot point is located at any point along the original optical axis between the light source and the sample plane, wherein the other optical axis is at a second angle of incidence with respect to a normal to the sample plane, and wherein the second angle of incidence is greater than the first angle of incidence.
2. 2. The method according to claim 1, Wherein the adjusted illumination distribution produced by the illumination subsystem at the sample plane has a highest intensity at a point at the center of the adjusted illumination distribution.
3. 3. The method according to claim 1, Wherein the light source and the at least one lens of the illumination subsystem are aligned along the original optical axis and, after rotation, along the other optical axis.
4. 4. The method of claim 1, further comprising: An excitation filter is disposed between the light source and the sample plane.
5. 5. The method of claim 1, further comprising: an imaging lens is disposed above the sample plane.
6. 6. The method of claim 5, further comprising: An emission filter is disposed between the imaging lens and the sample plane.
7. 7. The method according to claim 1, Wherein the sample plane is formed by an array of reaction chambers.
8. 8. The method according to claim 7, Wherein each reaction chamber in the array of reaction chambers is configured to contain a fluorescent dye such that the fluorescent dye produces fluorescence upon illumination by the illumination subsystem.
9. 9. The method according to claim 1, Wherein the light source is configured to generate visible light, infrared light, or ultraviolet light.
10. 10. The method according to claim 1, Wherein the light source is a light emitting diode.
11. 11. The method according to claim 1, Wherein the angle of rotation of the illumination subsystem depends on the first angle of incidence, the light source, the at least one lens, the position of the pivot point along the original optical axis, the distance between the light source and the at least one lens, and the distance between the light source and the sample plane.
12. 12. The method according to claim 11, Wherein the distance between the light source and the at least one lens is 60 mm; The first incident angle is 17 DEG, and The illumination subsystem is rotated 2.7 ° about the pivot point.
13. 13. The method according to claim 11, Wherein the distance between the light source and the at least one lens is 30 mm; The distance between the light source and the sample plane is 110 mm; The first incident angle is 22 DEG, and The illumination subsystem is rotated 1.3 ° about the pivot point.
14. 14. An optical system, comprising: An illumination subsystem comprising a light source and at least one lens, the illumination subsystem configured to be in a primary tilted position having an original optical axis at a first angle of incidence greater than 0 ° and less than 90 ° from a normal to a sample plane, wherein a reference illumination distribution is generated on the sample plane by the illumination subsystem in the primary tilted position; Wherein the illumination subsystem is rotatable about a pivot point to a secondary tilt position having a further optical axis until symmetry of an intensity distribution is improved in a case where an adjusted illumination distribution produced by the illumination subsystem at the sample plane is compared to a reference illumination distribution produced by the illumination subsystem at the original optical axis, wherein the pivot point is located at any point along the original optical axis between the light source and the sample plane, wherein the further optical axis is at a second angle of incidence with respect to a normal to the sample plane, and wherein the second angle of incidence is greater than the first angle of incidence.
15. 15. An optical system according to claim 14, Wherein the adjusted illumination distribution produced by the illumination subsystem at the sample plane has a highest intensity at a point at the center of the adjusted illumination distribution.
16. 16. The optical system of claim 14, further comprising: an excitation filter configured between the light source and the sample plane, and an imaging lens configured above the sample plane.
17. 17. An optical system according to claim 14, Wherein the illumination subsystem further comprises: a plurality of light sources; A plurality of lenses, and A plurality of excitation filters, an Wherein the optical system further comprises a plurality of emission filters; the plurality of excitation filters and the plurality of emission filters are configured for different wavelengths.
18. 18. An optical system according to claim 14, Wherein the angle of rotation of the illumination subsystem depends on the first angle of incidence, the light source, the at least one lens, the position of the pivot point along the optical axis, the distance between the light source and the at least one lens, and the distance between the light source and the sample plane.
19. 19. An optical system according to claim 18, Wherein the distance between the light source and the at least one lens is 60 mm; The first incident angle is 17 DEG, and The illumination subsystem is rotated 2.7 ° about the pivot point.
20. 20. An optical system according to claim 18, Wherein the distance between the light source and the at least one lens is 30 mm; The distance between the light source and the sample plane is 110 mm; The first incident angle is 22 DEG, and The illumination subsystem is rotated 1.3 ° about the pivot point.

Description

Optical system and method for illuminating a sample plane The application is a divisional application of patent application of application with application number 201980005960.8, which is filed on 5/25 th year 2020 and is named as an optical system and a method for irradiating a sample plane. Technical Field Aspects of the present disclosure relate to a method of illuminating a sample plane. Aspects of the disclosure may relate to an optical system. Background In certain biological applications, such as digital Polymerase Chain Reaction (PCR), an array of reaction chambers may contain a biological sample, such as deoxyribonucleic acid (DNA) or the like, and a fluorescent dye. Adjacent reaction chambers may be separated (zoned) by one or more baffles. In most practical cases, it may be desirable to have a consistent fluorescence signal (or at least approximately a consistent fluorescence signal) from all partitions within the array (or in the case of two or more arrays, a consistent fluorescence signal from all partitions across the array). By "uniform signal" is meant that when equal concentrations of dye are present in each zone, then each zone will produce equal fluorescence when illuminated by the source of the instrument. From an optical system design standpoint, to reconcile the fluorescent signals from each partition within the partitioned array, it is desirable to achieve uniform illumination onto the partitioned array. The resulting illumination distribution is typically non-uniform due to the fundamental nature of light emanating from its source as it propagates onto the screen. Fig. 1A is a schematic diagram depicting a state in which the illumination subsystem provides direct illumination onto the sample plane at normal incidence (i.e., 0 degree angle of incidence), which results in a non-uniform light distribution (center area brighter than edges). FIG. 1B is another schematic diagram depicting the use of a beam splitter (as is commonly done in fluorescence detection) to reflect light downward onto a sample plane. The reflection is simply a "mirror image" of the direct illumination. This therefore also results in the same type of non-uniformity at the sample plane. In some cases where there is practical significance in fluorescence detection, one may wish to illuminate the sample plane without using a beam splitter (e.g., to eliminate stray light problems associated with beam splitters, or to reduce the cost of the instrument by not including a beam splitter). In this case, as shown in fig. 2, one would illuminate the sample plane at oblique incidence (i.e., an angle of incidence >0 degrees). Fig. 2 is a schematic diagram showing oblique incidence illumination for fluorescence detection, producing an asymmetric light distribution at the sample plane. In this case, asymmetric non-uniformities are created, i.e. edges closer to the lens are brighter than edges further from the lens. Disclosure of Invention Various embodiments may provide a method of illuminating a sample plane. The method may include providing an illumination subsystem including a light source and at least one lens, the illumination subsystem having an optical axis at an angle of incidence greater than 0 ° and less than 90 ° from a normal to a sample plane. The method may further comprise rotating the illumination subsystem about a pivot point along the optical axis between the light source and the sample plane such that the adjusted illumination distribution produced by the illumination subsystem at the sample plane has a higher symmetry than a reference illumination distribution produced by the illumination subsystem at the sample plane without rotation about the pivot point. Various embodiments may provide an optical system. The optical system may include an illumination subsystem including a light source and at least one lens, the illumination subsystem having an optical axis at an angle of incidence greater than 0 ° and less than 90 ° from a normal to the sample plane. The illumination subsystem may be rotated or rotatable about a pivot point along the optical axis between the light source and the sample plane such that the adjusted illumination distribution produced by the illumination subsystem at the sample plane has a higher symmetry than a reference illumination distribution produced by the illumination subsystem at the sample plane without rotation about the pivot point. Drawings The invention will be better understood with reference to the detailed description when considered in conjunction with the non-limiting examples and the accompanying drawings, in which: Fig. 1A is a schematic diagram depicting a state in which the illumination subsystem provides direct illumination onto the sample plane at normal incidence (i.e., 0 degree angle of incidence), which results in a non-uniform light distribution (center area brighter than edges). FIG. 1B is another schematic diagram depicting the use of a beam splitter (as is common