An apparatus for guiding propagating light waves, comprising: a first plastic optical fiber cable comprising a first plastic optical fiber and a first jacket surrounding the first plastic optical fiber except for an end section of the first plastic optical fiber terminating at a first end face; a second plastic optical fiber cable comprising a second plastic optical fiber and a second jacket surrounding the second plastic optical fiber except for an end section of the second plastic optical fiber terminating at a second end face; and a plastic optical fiber splice assembly configured to optically couple the first and second end faces to each other, the plastic optical fiber splice assembly comprising: a first terminus having a first longitudinal section surrounding the end section of the first plastic optical fiber and a second longitudinal section surrounding a portion of the first jacket, the first terminus being made of thermoplastic material; a second terminus having a first longitudinal section surrounding the end section of the second plastic optical fiber and a second longitudinal section surrounding a portion of the second jacket, the second terminus being made of thermoplastic material; a splice alignment sleeve that surrounds the first longitudinal sections of the first and second termini and portions of the second longitudinal sections of the first and second termini, the splice alignment sleeve being made of thermoplastic material; a first crimp ring having a first longitudinal section surrounding and crimped onto one portion of the second longitudinal section of the first terminus and a second longitudinal section surrounding and crimped onto one end section of the splice alignment sleeve, the first crimp ring being made of metallic material; and a second crimp ring having a first longitudinal section surrounding and crimped onto one portion of the second longitudinal section of the second terminus and a second longitudinal section surrounding and crimped onto another end section of the splice alignment sleeve, the second crimp ring being made of metallic material. a first plastic optical fiber cable comprising a first plastic optical fiber and a first jacket surrounding the first plastic optical fiber except for an end section of the first plastic optical fiber terminating at a first end face; a second plastic optical fiber cable comprising a second plastic optical fiber and a second jacket surrounding the second plastic optical fiber except for an end section of the second plastic optical fiber terminating at a second end face; and a plastic optical fiber splice assembly configured to optically couple the first and second end faces to each other, the plastic optical fiber splice assembly comprising: a first terminus having a first longitudinal section surrounding the end section of the first plastic optical fiber and a second longitudinal section surrounding a portion of the first jacket, the first terminus being made of thermoplastic material; a second terminus having a first longitudinal section surrounding the end section of the second plastic optical fiber and a second longitudinal section surrounding a portion of the second jacket, the second terminus being made of thermoplastic material; a splice alignment sleeve that surrounds the first longitudinal sections of the first and second termini and portions of the second longitudinal sections of the first and second termini, the splice alignment sleeve being made of thermoplastic material; a first crimp ring having a first longitudinal section surrounding and crimped onto one portion of the second longitudinal section of the first terminus and a second longitudinal section surrounding and crimped onto one end section of the splice alignment sleeve, the first crimp ring being made of metallic material; and a second crimp ring having a first longitudinal section surrounding and crimped onto one portion of the second longitudinal section of the second terminus and a second longitudinal section surrounding and crimped onto another end section of the splice alignment sleeve, the second crimp ring being made of metallic material. a first terminus having a first longitudinal section surrounding the end section of the first plastic optical fiber and a second longitudinal section surrounding a portion of the first jacket, the first terminus being made of thermoplastic material; a second terminus having a first longitudinal section surrounding the end section of the second plastic optical fiber and a second longitudinal section surrounding a portion of the second jacket, the second terminus being made of thermoplastic material; a splice alignment sleeve that surrounds the first longitudinal sections of the first and second termini and portions of the second longitudinal sections of the first and second termini, the splice alignment sleeve being made of thermoplastic material; a first crimp ring having a first longitudinal section surrounding and crimped onto one portion of the second longitudinal section of the first terminus and a second longitudinal section surrounding and crimped onto one end section of the splice alignment sleeve, the first crimp ring being made of metallic material; and a second crimp ring having a first longitudinal section surrounding and crimped onto one portion of the second longitudinal section of the second terminus and a second longitudinal section surrounding and crimped onto another end section of the splice alignment sleeve, the second crimp ring being made of metallic material.