BS EN ISO 11807-2:2005 pdf – Integrated optics — Vocabulary — Part 2: Terms used in classification.
2.2 Types of function NOTE The types of function defined here are specified for elements, whereby they are valid for all corresponding component configurations. 2.2.1 passive integrated optical element element based on the principle of waveguiding and radiation interference， respectively, without external influence on the refractive index and ftted exclusively with optical inputs and outputs NOTE This element is employed for changing the di- rection, distributing, combining, transforming and filtering of guided radiation waves. 2.2.2 controllable integrated optical element element which can be influenced by various physical effects [e.g. electro-optical, acousto-optical, piezo- optical, thermo-optic or electro-absorptive material characteristics which can be used to change the (complex) refractive index] NOTE In the case of electro-optical control, the refrac- tive index can be changed by the penetration of an electric field, or acousto-optical control by a surface acoustic wave (SAW). 2.2.3 , active integrated optical element element based on photo-effect and emission
2.3 Passive elements and chips 2.3.1 slab waveguide waveguide which confines the radiation only perpen- dicular to the substrate 2.3.2 strip waveguide element which confines the radiation in a two-dimen- sional cross-sectional area perpendicular to the sub- strate surface along a one-dimensional path NOTE In general the core or, in the case of a graded index profile, the corresponding core area, may be formed as: embedded channel [see Figure 2a)] or buried channel [see Figure 2b]; ridge on a substrate [see Figure 2c); ridge in a waveguiding layer [see Figure 2d)] or rib on a waveguiding layer [strip-loaded waveguide; see Figure 2e)]. 2.3..3 branch element which divides an input strip waveguide into multiple output strip waveguides NOTE Depending on the application, a distinction is made between a divider usually a 1 x M divider and a com- biner, usually a N x 1 combiner. 2.3.4 tap element which couples a given portion of radiation out of a strip waveguide into another waveguide branch- ing out of the side of the original waveguide
2.3.6 directional coupler four-port element consisting of a pair of strip waveguides in which the fields are mutually coupled and the input and output ends diverge from one an- other NOTE 1 The two waveguides may be closely spaced, intersect, or cross each other at an acute angle. NOTE 2. The function is based on the principle of peri- odic coupling of radiation by interference. They can be fab- ricated as either a passive or controllable element. Directional couplers where the waveguides intersect each other (at an acute angle) are also given the designation X-coupler. 2.3.7 3-dB coupler four-port element which divides the entering power of radiation equally between both output waveguides 2.3.8 Nx M star coupler element in which the radiant power of N input waveguides is distributed equally amongst M output waveguides NOTE The star coupler can be configured from net- worked Y-branches and/or 3-dB couplers or a multi-mode waveguide section. 2.3.9 waveguide intersection element consisting of two strip waveguides which in- tersect one another NOTE 1 If the angle of intersection is large enough (ideal case 90%), then no mutual interference occurs between the guided waves in the individual waveguides.
2.3.12 polarization converter element in which at least a part of the input (TE-, TM-) eigenmode of the waveguide, which is usually bire- fringent, is transformed into the orthogonal eigenmode NOTE In a TE/TM-converter a complete conversion from one eigenmode into the orthogonal eigenmode takes place. 2.3.13 TE/TM mode splitter element which splits the TE- and TM-modes at the in- put waveguide and which guides them into corre- sponding output waveguides NOTE The relationship between the radiant power P at the selected output to radiant power Pt at the non- selected output is given by the designation mode splitting ratios, on a logarithmic scale with S = 10 lg(P/Pf) dB. 2.3.14 waveguide mirror mirror which reflects, on a flat or curved surface, the guided radiation wave in the input waveguide into an output waveguide usually of different direction or ver- tically out of the substrate NOTE For example, for detector or laser input cou- pling. 2.3.1 5 integrated optical Mach-Zehnder interferometer element consisting of two Y-branches or directional couplers (usually 3-dB couplers) arranged opposite to one another and connected by two strip waveguides