Abstract: An optical branch module including a glass block, an input/output gradient index lens, an output gradient index lens, a beam splitter film, a mirror film, an input optical fiber, a first output optical fiber that extracts input light from the input optical fiber reflected by the beam splitter film as first output light, and a second output optical fiber that extracts light passed through the beam splitter film passed through the glass block, reflected by the mirror film, passed through the glass block again, and input from the other end of the output gradient index lens as second output light.

Abstract: The photo module is provided with an incident light fiber guiding light, a gradient index lens having an optical axis different from the incident light fiber, having a period length larger than a ¼ period length and smaller than a ½ period length with respect to the wavelength of the incident light, joined to the incident light fiber on a surface forming a finite angle with a surface vertical to the optical axis, and having, as a light exit surface of emitting light, a surface substantially vertical to the optical axis, and a light receiving element disposed at a position where the emitting light is collected and measuring the strength of the emitting light.

Abstract: The present invention provides an array-type photo module including a filter, which, in each channel, transmits therethrough a portion of emitted light from an incident optical fiber on the opposite side of a gradient-index lens array and reflects another portion of the emitted light from the incident optical fiber toward the gradient-index lens array, and a light-shielding member which is arranged on the opposite side of the filter from the gradient-index lens array, so as to be spaced from the filter and, in each channel, has an opening passing therethrough transmitted light from the filter on the opposite side of the filter. The array-type photo module is easily and inexpensively manufactured, and may be used in a high-density array, with low crosstalk.

Abstract: PROBLEM An object of the present invention is to easily and inexpensively manufacture an array-type photo module and, in addition, coexist high-density array and low crosstalk. SOLUTION The present invention provides an array-type photo module M including a filter 31, which, in each channel, transmits therethrough a portion of emitting light from an incident optical fiber 11 on the opposite side of a gradient-index lens array 2 and reflects another portion of the emitting light from the incident optical fiber 11 toward the gradient-index lens array 2, and a light-shielding member 32 (33) which is arranged on the opposite side of the gradient-index lens array 2 of the filter 31 so as to be spaced from the filter 31 and, in each channel, has an opening 34 (35) passing therethrough transmitted light from the filter 31 on the opposite side of the filter 31.