A coaxial photoelectric sensor (106, 200a, 200b, 400a, 400b, 400c, 400d), comprising: an optical emitter (204, 404) disposed on a printed circuit board (202, 402), and configured to generate an illumination signal; a reflection optical component (208, 310, 408a, 408b, 432) optically aligned with the optical emitter (204, 404) to receive and reflect the illumination signal to generate a first reflected illumination signal; a reflective optical component (218, 228, 418, 504, 510, 512) optically aligned with the reflection optical component (208, 310, 408a, 408b, 432) so as to reflect the first reflected illumination signal received from the reflection optical component (208, 310, 408a, 408b, 432) to produce a second reflected illumination signal; a target reflector component (104a, 108, 222, 230, 422) optically aligned with the reflective optical component (218, 228, 418, 504, 510, 512) to coaxially reflect the second reflected illumination signal received from the reflective optical component (218, 228, 418, 504, 510, 512); and an optical detector (206, 406) disposed on the PCB (202, 402), and configured to generate an electrical signal in response to receiving the illumination signal coaxially reflected by the target reflector component (104a, 108, 222, 230, 422), characterized in that the reflection optical component (208, 310, 408a, 408b, 432) is configured to cause the first reflected illumination signal to be focused at a focal plane (214, 320, 414) between the reflection optical component (208, 310, 408a, 408b, 432) and the reflective optical component (218, 228, 418, 504, 510, 512), thereby producing a virtual secondary illumination source (216, 318, 416) at the focal plane. an optical emitter (204, 404) disposed on a printed circuit board (202, 402), and configured to generate an illumination signal; a reflection optical component (208, 310, 408a, 408b, 432) optically aligned with the optical emitter (204, 404) to receive and reflect the illumination signal to generate a first reflected illumination signal; a reflective optical component (218, 228, 418, 504, 510, 512) optically aligned with the reflection optical component (208, 310, 408a, 408b, 432) so as to reflect the first reflected illumination signal received from the reflection optical component (208, 310, 408a, 408b, 432) to produce a second reflected illumination signal; a target reflector component (104a, 108, 222, 230, 422) optically aligned with the reflective optical component (218, 228, 418, 504, 510, 512) to coaxially reflect the second reflected illumination signal received from the reflective optical component (218, 228, 418, 504, 510, 512); and an optical detector (206, 406) disposed on the PCB (202, 402), and configured to generate an electrical signal in response to receiving the illumination signal coaxially reflected by the target reflector component (104a, 108, 222, 230, 422), characterized in that the reflection optical component (208, 310, 408a, 408b, 432) is configured to cause the first reflected illumination signal to be focused at a focal plane (214, 320, 414) between the reflection optical component (208, 310, 408a, 408b, 432) and the reflective optical component (218, 228, 418, 504, 510, 512), thereby producing a virtual secondary illumination source (216, 318, 416) at the focal plane.