An endoscopic probe extending from a proximal end to a distal end thereof, and configured to be inserted in a tubular lumen to observe a sample is disclosed. The probe includes a first waveguide enclosed within an inner sheath and extending from the proximal end to the distal end along an axis of the inner sheath; and a plurality of second waveguides having at least the distal ends thereof arranged in one or more rings around the inner sheath to surround the distal end of the first waveguide. At the distal end, the axis of each of the second waveguides is tilted with respect to the axis of the first waveguide by a tilt angle which can be adjustable. This novel endoscopic probe has a resultant numerical aperture larger than the numerical aperture of each of the second waveguides, and it may be applicable to forward-viewing spectrally encoded endoscopes (SEE).