|
 |
 |
 |
 |
 |
• |
First
commercial infra-red film became available around 1931.
|
|
• |
Its earliest
applications were primarily for scientific purposes;
|
|
|
as an
investigative tool in criminology, in ophthalmology and
|
|
|
other medical
fields, in the exploration of space, and in aerial
|
|
|
survey work.
|
|
|
|