This technique is well-worth mastering for home cooks, as it's an easy way to cope successfully with thick steak and chop-style cuts of beef, pork and other meats. Step 1 Take the sirloin filets out of the refrigerator 45 to 120 minutes before you plan to cook them; chilled beef doesn't cook evenly.
The refractive index of current eyeglass lens materials ranges from 1.498 (CR-39 plastic) to 1.74 (a specific variety of high-index plastic). So for the same prescription power and lens design, a lens made of CR-39 plastic will be the thickest lens available, and a 1.74 high-index plastic lens will be the thinnest.
noun. The lens in these glasses are blue. The lens in these glasses are blue. The definition of a lens is a piece of glass or other hard clear material molded with one side flat and the other curved or both sides curved that forms an image by bringing together or spreading the light that passes through it.1  An example of lens is the clear pieces covering the eyes in eye glasses.ens-Computer Definition. The glass or plastic elements that focus light onto analog film or a digital sensor in a still or video camera. Lens quality is just as important in digital cameras as it was in the Daguerreotype cameras in the 1800s.