# Converting a Common Document Scanner to a Multispectral Scanner

## TL;DR

This paper presents a method to convert a standard document scanner into a multispectral scanner by modifying its light source, enabling enhanced document analysis for verification purposes.

## Contribution

The paper introduces a practical approach to retrofit existing scanners with multispectral capabilities using external LEDs, expanding their application scope.

## Key findings

- Prototype successfully captures multispectral images of documents.
- System is portable and suitable for verifying documents, cheques, and bank notes.
- Demonstrates feasibility of low-cost multispectral scanning with standard hardware.

## Abstract

We propose the construction of a prototype scanner designed to capture multispectral images of documents. A standard sheet-feed scanner is modified by disconnecting its internal light source and connecting an external multispectral light source comprising of narrow band light emitting diodes (LED). A document is scanned by illuminating the scanner light guide successively with different LEDs and capturing a scan of the document. The system is portable and can be used for potential applications in verification of questioned documents, cheques, receipts and bank notes.