Optical polymer films and methods for casting the same

A method comprising:

• dispensing a photocurable material onto a first surface of a first mold;
• positioning the first mold and a second mold such that the first surface and a second surface of the second mold are separated by a gap;
• obtaining measurement information indicative of a pressure at each of at least three locations between the first and second molds during use of the system, wherein obtaining the measurement information comprises:
• determining, using a first pressure sensor, a first pressure applied to a first mechanical spacer,
• determining, using a second pressure sensor, a second pressure applied to a second mechanical spacer, and
• determining, using a third pressure sensor, a third pressure applied to a third mechanical spacer,
• wherein the first mechanical spacer, the second mechanical spacer, and the third mechanical spacer are disposed at different locations between the first and second molds and/or at different locations along a periphery of the first and second molds, and
• wherein the first mechanical spacer is disposed above the first pressure sensor, wherein the second mechanical spacer is disposed above the second pressure sensor, and wherein the third mechanical spacer is disposed above the third pressure sensor;
• and
• determining a first distance between the first and second molds surfaces at a first location based on the first pressure applied to the first mechanical spacer;
• determining a second distance between the first and second molds surfaces at a second location based on the second pressure applied to the second mechanical spacer;
• determining a third distance between the first and second molds surfaces at a third location based on the third pressure applied to the third mechanical spacer, wherein the first, second, and third locations are different;
• and
• controlling the gap between the first and second molds surfaces based on the measurement information.