Development of an optical sound reproduction system for negative phonograph cylinders

负型留声机滚筒光学声音再现系统的开发

基本信息

批准号：
09555006
负责人：
UOZUMI Jun
金额：
$ 4.35万
依托单位：
HOKKAIDO UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
1997
资助国家：
日本
起止时间：
1997 至 1998
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-09555006/
关键词：
Wax cylinder Galvano Optical reproduction Laser-beam reflection PSD Phonograph Folk music Otojiro Kawakami

项目摘要

It was found recently that many negative phonograph cylinders have been preserved in Berlin, Germany. Since, in the negative cylinder, sound information is encoded in convex portions of the inside wall of the cylinder, a conventional phonograph is inapplicable to the sound reproduction. In the present study, we have developed an optical sound reproduction system for the negative cylinders.1. Compact optical headSound information is recovered by detecting height variations of the sound track on the inside wall of the negative, To this end, a compact optical head to be inserted into the cylinder was designed and constructed using a laser diode, small lenses, mirrors, a beam splitter and a PSD.A relay optics consisting of a lens and a pinhole was inserted in the detection optics to reject stray light effectively and to improve an SNR of reproduced sounds.2. Driving unitIn the driving unit, the negative is held by inserting it into a larger holding cylinder and by fixing it to the holding cylinder with six screws. The holding cylinder is rotated by a DC motor, and the cylinders and motor are mounded on the translation stage, which is driven by a pulse motor to keep a tracking by the laser beam.3. Entire system and sound reproductionAbove components were combined into a system and controlled by a control unit, and the final performance of the system was examined and verified. Sounds were reproduced successfully from some old negative cylinders, in which cylinders of koto and shamisen played and recorded by a Japanese old company of drama shows, led by Otojiro Kawakami, are included.

最近发现，德国柏林保存有许多留声机负片滚筒。由于在负圆筒中，声音信息被编码在圆筒内壁的凸出部分中，所以传统的留声机不适用于声音再现。在本研究中，我们开发了一种用于负圆筒的光学声音再现系统。 1．紧凑型光学头通过检测底片内壁上音轨的高度变化来恢复声音信息。为此，设计并构造了一个插入圆柱体的紧凑型光学头，使用激光二极管、小透镜、镜子、检测光学器件中插入了由透镜和针孔组成的中继光学器件，可有效抑制杂散光，提高再现声音的信噪比。 2．驱动单元在驱动单元中，通过将负片插入较大的固定筒中并用六个螺钉将其固定到固定筒上来固定负片。保持气缸由直流电机驱动旋转，气缸和电机安装在平移台上，平移台由脉冲电机驱动，以保持激光束的跟踪。 3．整个系统和声音再现将上述组件组合成一个系统并由控制单元控制，并对系统的最终性能进行检查和验证。一些旧的底片成功地再现了声音，其中包括以川上乙二郎为首的日本老剧团演奏和录制的古筝和三味线的底片。