Hybrid optical fiber, endoscopic system, and method for examining a sample

An endoscopic system for examining a sample, comprising:

• a hybrid optical fiber comprising:
• a plurality of fiber cores,
• a first cladding enclosing the plurality of fiber cores, and
• a second cladding enclosing the first cladding, wherein the plurality of fiber cores have a first refractive index, the first cladding has a second refractive index and the second cladding has a third refractive index, wherein the first refractive index is greater than second refractive index, and the second refractive index is greater than the third refractive index;
• and
• an optical arrangement comprising:
• a coherent light source configured to introduce light into a proximal end of the hybrid optical fiber such that the plurality of fiber cores and the first cladding function as a multimode optical fiber, and
• a photodetector comprising a plurality of pixels configured to detect the light emerging from individual ones of the plurality of fiber cores,
• wherein the endoscopic system is further adapted to operate in:
• a first operating mode in which the coherent light source is used to excite light modes in the hybrid optical fiber functioning as the multimode optical fiber in such a way that individual object points in the sample are illuminated one after another, and the light response emitted by the object points is detected by the photodetector, and
• a second operating mode in which the coherent light source is used to illuminate objects in the sample, and the light response emitted by the objects is detected separately for each of the plurality of fiber cores by the photodetector.

An endoscopic system for examining a sample, comprising:

• a hybrid optical fiber comprising:
• a plurality of fiber cores,
• a first cladding enclosing the plurality of fiber cores, and
• a second cladding enclosing the first cladding, wherein the plurality of fiber cores have a first refractive index, the first cladding has a second refractive index and the second cladding has a third refractive index, wherein the first refractive index is greater than second refractive index, and the second refractive index is greater than the third refractive index;
• and
• an optical arrangement comprising:
• a coherent light source configured to introduce light into a proximal end of the hybrid optical fiber such that the plurality of fiber cores and the first cladding function as a multimode optical fiber, and
• a photodetector comprising a plurality of pixels configured to detect the light emerging from individual ones of the plurality of fiber cores,
• wherein the optical arrangement comprises a further light source configured to introduce further light into at least one of the plurality of fiber cores or the first cladding, and
• wherein the further light source has a plurality of partial light sources, and wherein the partial light sources are arranged in an array and assigned to the plurality of fiber cores of the hybrid optical fiber, and wherein the objects in the sample are illuminated by the additional light source.

An endoscopic system for examining a sample, comprising:

• a hybrid optical fiber comprising:
• a plurality of fiber cores,
• a first cladding enclosing the plurality of fiber cores, and
• a second cladding enclosing the first cladding, wherein the plurality of fiber cores have a first refractive index, the first cladding has a second refractive index and the second cladding has a third refractive index, wherein the first refractive index is greater than second refractive index, and the second refractive index is greater than the third refractive index;
• and
• an optical arrangement comprising:
• a coherent light source configured to introduce light into a proximal end of the hybrid optical fiber such that the plurality of fiber cores and the first cladding function as a multimode optical fiber, and
• a photodetector comprising a plurality of pixels configured to detect the light emerging from individual ones of the plurality of fiber cores,
• wherein the hybrid optical fiber includes a first part and a second part, and wherein the first part and the second part are connected to one another in a detachable manner via a connecting element.

A method for examining a sample using an endoscopic system which comprises a hybrid optical fiber comprising (i) a plurality of fiber cores, (ii) a first cladding enclosing the plurality of fiber cores, and (iii) a second cladding enclosing the first cladding, wherein the plurality of fiber cores have a first refractive index, the first cladding has a second refractive index and the second cladding has a third refractive index, wherein the first refractive index is greater than second refractive index, and the second refractive index is greater than the third refractive index, the endoscopic system further comprising an optical arrangement comprising (i) a coherent light source configured to introduce light into a proximal end of the hybrid optical fiber such that the plurality of fiber cores and the first cladding function as a multimode optical fiber, and (ii) a photodetector comprising a plurality of pixels configured to detect the light emerging from individual ones of the plurality of fiber cores, wherein the method comprising:

• inserting the hybrid optical fiber of the endoscopic system into the sample which is initially immovable, wherein at least one of the optical arrangement or the first optical subassembly of the endoscopic system is connected to the hybrid optical fiber;
• introducing light into the plurality of fiber cores and the first cladding of the hybrid optical fiber using the coherent light source, wherein the hybrid optical fiber functions as a multimode optical fiber, wherein a number of object points in the sample are illuminated one after another through the hybrid optical fiber;
• and
• detecting the light response emitted by the object points via the hybrid optical fiber using the photodetector;
• moving the sample, wherein the optical arrangement or the second optical subassembly of the endoscopic system is connected to the hybrid optical fiber;
• introducing light into at least one of the plurality of fiber cores or the first cladding using the coherent light source or a further light source so as to illuminate objects at the distal ends of the fiber cores;
• and
• detecting a light response emitted from the objects which is passed through the plurality of fiber cores by the pixels of the photodetector.