Methods for optimizing graded index fiber length to improve image quality

A method for manufacturing a graded index fiber, comprising:

• receiving an optical assembly comprising an input fiber, an output fiber, and a graded index fiber spliced between the input fiber and the output fiber,
• wherein the graded index fiber has a pitch length and a processed length;
• delivering input light into an input end of the input fiber;
• monitoring output light at an output end of the output fiber, wherein the monitoring comprises actively monitoring the output light;
• and
• expanding a core diameter of the graded index fiber while shortening the processed length of the graded index fiber and actively monitoring the output light until one or more measurements of the output light at the output end of the output fiber indicate that the output light is a perfect image of the input light,
• wherein the processed length of the graded index fiber is N times the pitch length when the one or more measurements indicate that the output light is a perfect image of the input light, where N is an integer, a half-integer, or a quarter-integer.

A method for manufacturing a graded index fiber, comprising:

• receiving an optical assembly comprising an input fiber, an output fiber, and a graded index fiber spliced between the input fiber and the output fiber,
• wherein the graded index fiber has a pitch length and a processed length;
• delivering input light into an input end of the input fiber;
• monitoring output light at an output end of the output fiber, wherein the monitoring comprises actively monitoring the output light;
• and
• altering a core diameter and the processed length of the graded index fiber while actively monitoring the output light until one or more measurements of the output light at the output end of the output fiber indicate that the output light is a perfect image of the input light,
• wherein the processed length of the graded index fiber is N times the pitch length when the one or more measurements indicate that the output light is a perfect image of the input light, where N is an integer, a half-integer, or a quarter-integer.