ranma 欄間

A transom. A rectangular opening, longer in the horizontal direction, constructed between the lintels *kamoi 鴨居 or uchinori nageshi 内法長押, of the frame for sliding screens and the ceiling. Transoms may also be found at the boundary between a veranda and the interior of a dwelling, under the ridges of a gate, on a fence for above the main entrance *genkan 玄関 of a structure.
Transoms filled with lattice or muntins in a variety of arrangements are called latticework transoms renji ranma 連子欄間. Renji ranma often have small screens *shōji 障子, called shōji ranma 障子欄間, slide horizontally on both sides and have a central strut where they meet when closed. This type of ranma was popular from the 12th through the 14th century. Flat openwork *sukashibori 透彫 became common in the 15th century. From the latter part of the 16th century to approximately the end of the 17th century, elaborate trees, figures and scenes from history and legend filled the transom spaces, especially in temple halls of the *shoin 書院 style. In spite of transoms providing a place for decorative expression, they did not lose their function of increasing light and air circulation.
There are many kinds of decoration used in the transoms. The most common is plain latticework kōshi ranma 格子欄間, like that used on the inside of the doors at Byōdōin *Hōōdō 平等院鳳凰堂 (1053) in Kyoto. Another common type of lattice is laid diagonally forming a lozenge pattern hishigōshi ranma 菱格子欄間. There is also the *yumi ranma 弓欄間, which has curvilinear slats set into a transom. The osa ranma 筬欄間 has closely-spaced vertical bars and a small number of horizontals set across them. When the same type of lattice is used for transoms above a veranda, it is called saya ranma 鞘欄間. Transoms called *ita ranma 板欄間 have thin boards with openwork designs cut into them or arranged decoratively with an open area. The bamboo node transom *take-no-fushi ranma 竹の節欄間, has posts that are grooved at the base and neck to resemble bamboo nodes. The intervals between the posts have double wood strips that run diagonally.