Hello, I've been using the calculator lens to read display screens for 30 years. It's much easier to use than the CRT lens because it is much lighter in weight. Perhaps the crt lens works on more types of monitors, but I've never done any side by side comparisons with the calculator lens. Chris To unsubscribe at any time, just send a message to: optacon-l-request@xxxxxxxxxxxxx with the word "unsubscribe" (without the quotes) in the message subject. Tell your friends about the list. They can subscribe by sending a message to: optacon-l-request@xxxxxxxxxxxxx with the word "subscribe" (without the quotes) in the message subject.