What steps will reproduce the problem? 1. Put Light level sensor for measurement light level between light and sensor at the other side of page.

2. Calibrate volume of light for the first or second page

3. If volume of measurement smaller than for first page - stop the system and start again by the Emergency control button

What is the expected output? What do you see instead?

If pages are sticking together or folding we will see it and system will stop.

What version of the product are you using? On what operating system? I use flatbed scanners Plustek. My experience of scanning more than 3 00 000 pages of books and magazines

Please provide any additional information below.

Lead Engineer of Soil Physics and Reclamation Department Faculty of Soil Science Moscow State University Moscow

Thank you for the suggestion. One challenge with using optical sensors is ink, which dramatically affect signal attenuation. Most commercially available sensors for double page detection are ultrasonic.