Concentric Electrodes
Concentric bipolar electrodes are excellent for shielded macro recording, as well as evoked potentials. They are especially well suited for bipolar stimulation. The tungsten electrode is sharpened to a point and is 75μm in diameter. The outer stainless steel conductor is insulated with Polyimide tubing to within 0.2mm of the end of the stainless steel tube. This electrode is also available without the outer Polyimide insulation. A comparison of the concentric electrodes is at the bottom of the page.
Concentric electrodes with outer polyimide insulation
Concentric electrodes without insulation
This figure shows an insulated metal conductor with an exposed concentric surface.
Concentric Electrodes* Comparison Chart
Tungsten
| Item | Metal Core | Length | Impedance | Probe Outer Diameter (total) |
Tip Diameter |
Core Diameter |
Y dim | X dim. w/polyimide |
| TM33CCNON | Tungsten | 3” (76) | 10-15K | 0.013” uninsulated (325µm) | 3-4µm | .003” (76µm) | 0.4 mm | .005” (127µm) |
| TM33CCINS | Tungsten | 3” (76) | 10-15K | 0.016” insulated (400µm) | 3-4µm | .003” (76µm) | 0.4 mm | .005” (127µm) |
| TM33CCINS-B | Tungsten | 3" (76) | 10-15K | 0.016" insulated (400µm) | 3-4µm Blunt | .003" (76µm) | 0.4 mm | .005" (127µm) |
| TM53CCINS | Tungsten | 5” (127) | 10-15K | 0.018” insulated (450µm) | 3-4µm | .005” (127µm) | 0.4 mm |
.008” (203µm) |
*All have a stainless steel outer shaft.
Pt/Ir and Pt/IR NS fine
| Item | Metal Core | Length | Impedance | Probe Outer Diameter (total) |
Tip Diameter |
Core Diameter |
Y dim | X dim. w/polyimide |
| PTM23CC001NON | Pt/Ir | 2” (51) | 10K | 0.020” uninsulated (525µm) | 3-4µm | 0.01” (254µm) | 0.4 mm | .014” (356µm) |
| PTM23CC02INS | Pt/Ir | 2” (51) | 10K | 0.020” insulated (525µm) | 3-4µm | 0.01” (254µm) | 0.4 mm | .014” (356µm) |
| PTM3CC02INS | Pt/Ir NS fine | 3” (76) | 200K | 0.013” insulated (325µm) | 2-4µm | 0.002” (50.8µm) | .25 mm | .004” (114µm) |
*All have a stainless steel outer shaft.