BPI®  Advanced Computer Gradient IV™ Programs

Program 0: Solid 
The operator enters the amount of time for the lens to be immersed in the dye. The computer dips the lens into the solution at high speed and then agitates it up and down by a few millimeters so that the fluid touching the lens is always at full strength. This is the fastest procedure for dyeing a lens a solid color. There is no minimum cycle time, the lens bobs up and down until the requested time expires.

Program 1: Parabolic
This program produces a lens in which the characteristic time-distance curve is parabolic. In general, a parabolic program cycle produces a higher contrast gradient than a linear cycle, but not so much as the cubic cycle described below. Minimum execution time for this program is about 48 seconds.

Program 2: Parabolic - Lower Light
This program has the same general features as number 1 but differs in that the lens dips more quickly at the end of the cycle, thus producing a smoother fade between the clear and colored part of the lens.

Program 3: Cubic 
This program produces gradients whose time-distance curves are cubic in shape. It produces the most clearly visible gradients of any in this series and creates a subjective impression that the "turning point" between dark and light is nearer the dark side of the lens.

Program 4: 4 Stroke Process
This program emulates a mechanical 4- stroke gradient.

Program 5: 
Similar to programs 1 and 3, but suitable for longer timed gradients. Program starts more quickly and stops more gradually. It produces a uniformly dark top with less gradient at the bottom. There is a fast dip at the end to minimize line formation.

Program 6: 
Similar to program 5, but less aggressive.