Helium Lines (2.05 – 2.50 microns)
Infrared Helium Lines
| Atomic Line | Transition | Wavelength (um) |
| HEI | 2P-2S,1Po-1S | 02.0587 |
| HEI | 4S-3P,3S-3Po | 02.1126 |
| HeI | 3pP-4sS | 02.1132 |
| HEI | 4S-3P,1S-1Po | 02.1138 |
| HEII | 25-9 | 02.1195 |
| HEII | 24-9 | 02.1469 |
| HEI | 7S-4P,3S-3Po | 02.1500 |
| HEI | 7F-4D,3Fo-3D | 02.1614 |
| HeI | 4dD-7fF | 02.1617 |
| HEI | 7F-4D,1Fo-1D | 02.1623 |
| HEII | 14-8 | 02.1653 |
| HeI | 4-7 | 02.166 |
| HEII | 23-9 | 02.1786 |
| HEI | 7D-4P,1D-1Po | 02.1847 |
| HEII | 10-7 | 02.1891 |
| HEII | 22-9 | 02.2155 |
| HEI | 7S-4P,1S-1Po | 02.2290 |
| HEII | 21-9 | 02.2601 |
| HEII | 10LIMIT | 02.2778 |
| HEI | 6P-4S,1Po-1S | 02.3069 |
| HEII | 20-9 | 02.314 |
| HEII | 13-8 | 02.348 |
| HEII | 19-9 | 02.3788 |
| HEII | 18-9 | 02.4606 |
| HEI | 6D-4P,3D-3Po | 02.4734 |
| HEII | 17-9 | 02.5641 |