High-Density Fiber-optic Cannula features implantable fibers in a square or hexagonal pattern of 7, 9 or 19 holes. The optical fiber array tailored for selected brain areas is built by placing fibers into the nearest holes. The optical fiber protrusion of each fiber within the array is factory set to the desired length. The insertion of the cannula array into the brain tissue is facilitated if fiber tips are angled, conical or taper. On the back of the cannula body is a receptacle with an orientation guiding pin. High-Density Fiber-optic Cannula has up to 19 separate optical fiber connections for photometry recordings and/or optogenetics stimulation.

The matching fiber-optic patch cord and its multiple fiber connector are made with the same hexagonal pattern as the cannula itself. The connector is securely fastened to the cannula array with a threaded barrel. The other end of the fiber-optic patch cord is made to fit the sample port of the optical recording and/or stimulation system.

For 2 or 3 brain targets, single-site optogenetics and/or fiber photometry systems can be used for each fiber within the array. For 4 to 19 brain targets, the Doric Bundle-imaging Fiber-photometry system, where the signals from each fiber within the bundle are re-imaged on a CMOS or sCMOS chip, is more practical.