Miniature fiberoptic bend device and method

A joint assembly comprising

• a routing device for changing the direction of a fiberoptic path from a first axis to a second axis, said routing device comprising
• a short length of low-loss optical fiber having first and second directed fiber portions aligned respectively with said first and second axes and a mid-fiber portion integral with and extending through an arc of radius of the order of two centimeters or less between said first and second directed fiber portions,
• said mid-portion of fiber being in a treated state that reduces likelihood of mechanical failure of said routing device over time without introducing substantial optical loss,
• and an outer member coupled to said optical fiber for fixing said first and second directed fiber portions along said first and second axes, respectively, said outer member serving to protect said first and second directed fiber portions and said mid-portion from the environment,
• wherein said first and second directed-fiber portions are secured in respective members of a joint which are movable with respect to each other to a limited extent with corresponding bending of said mid-fiber portion in the region of said arc.

A joint assembly comprising a routing device for changing the direction of a fiberoptic path from a first axis to a second axis, said routing device being configured in the form of a slip joint,

• said routing device comprising
• a short length of low-loss optical fiber having first and second directed fiber portions aligned respectively with said first and second axes and a mid-fiber portion integral with and extending through an arc of radius of the order of two centimeters or less between said first and second directed fiber portions,
• said mid-portion of fiber being in a treated state that reduces likelihood of mechanical failure of said routing device over time without introducing substantial optical loss,
• and an outer member coupled to said optical fiber for fixing said first and second directed fiber portions along said first and second axes, respectively, said outer member serving to protect said first and second directed fiber portions and said mid-portion from the environment,
• wherein said fiber in said mid-portion is bent into the form of a helical coil such that when said first and second directed fiber portions move toward each other said helical coil is compressed and when said first and second directed fiber portions move away from each other said helical coil is expanded.

A joint assembly comprising a routing device for changing the direction of a fiberoptic path from a first axis to a second axis, said routing device being configured in the form of a rotary joint,

• said routing device comprising
• a short length of low-loss optical fiber having first and second directed fiber portions aligned respectively with said first and second axes and a mid-fiber portion integral with and extending through an arc of radius of the order of two centimeters or less between said first and second directed fiber portions,
• said mid-portion of fiber being in a treated state that reduces likelihood of mechanical failure of said routing device over time without introducing substantial optical loss,
• and an outer member coupled to said optical fiber for fixing said first and second directed fiber portions along said first and second axes, respectively, said outer member serving to protect said first and second directed fiber portions and said mid-portion from the environment,
• wherein said directed portions of said fiber are secured in members of a rotatable joint, said members being rotatable with respect to each other about an axis defined by said fiber in said mid-portion, said rotation twisting said fiber.

A method of making a routing device for changing the direction of a fiberoptic path from a first axis to a second axis, said method comprising the steps of:

• providing a length of low-loss optical fiber having first and second directed fiber portions;
• reducing the diameter of a mid-portion of said fiber a substantial amount relative to the diameter of said directed fiber portions;
• bending said fiber in said mid-portion through an arc of radius of the order of 2 cm or less so that said first and second directed fiber portions are aligned with the first and second axes, respectively,
• said steps of bending and reducing being performed in manner reducing likelihood of mechanical failure over time without introducing substantial optical loss.