.ILT File

The ilt file extension is mainly related to SpectrILight III, a spectroradiometer devices and used for their default saved spectrum data file in binary format.

Seems like older products from International Light Technologies. Used to measure light.

This ilt file type entry was marked as obsolete and no longer supported file format.

This type of file is no longer actively used and is most likely obsolete. This is typically the case for system files in old operating systems, file types from long discontinued software, or previous versions of certain file types (like documents, projects etc.) that were replaced in higher versions of their original programs.

How to open:

You can import these files to SpectrILight III software bundled together with the spectroratiometer.

How to convert:

Probably cannot be converted to anything else.