什麼是環線感應系統? What is a loop system?

環線感應系統是個輔助聽力的工具，可以與助聽器一起使用。它也被稱為「線圈」或是「T掣」。基本上是一圈鐵絲，繞在聽障朋友們需要聽的表面上來協助聽力。鐵線圈是與特殊設計過的音箱連線。而這特殊的音箱會跟公共廣播系統、麥克風或是一些能播放聲音的工具如:磁帶錄音機、電視或是收音機來連線。

The loop system is an assistive listening device that works along with your hearing aid. It may also be referred to as the telecoil, or T-system.

It is basically a loop of wire installed around the perimeter of an area where hearing impaired people may need listening assistance. The loop of wire is connected to the output of a specially designed audio amplifier. The amplifier may be connected to an existing public address system, microphone, or other audio source such as a tape recorder, television receiver or radio.

環線感應系統的目的:

• 降低外部噪音的引響。助聽器裡的環線感應系統必須開啟才能對外連線。

運作方式:

• 特殊的音箱會在鐵絲圈裡製造一波電流。這電流會製造一個磁場，而這磁場變化的方式如同聲音的音量被提高的方法一樣。這磁場可在微小的線圈內產生，而這微小的線圈可被安裝在助聽器裡或是其他特殊的接收裝置上, 想要聽到較大聲的朋友，只需要切換到T或是在助聽器上線圈的圖示，在遙控器上按下T，或是使用有特殊的環線感應接收器耳機。

Aim of the loop system:

• To help overcome background noise. The loop system must be activated in your hearing aid for you to be able to connect.

How it works:

• The amplifier causes an electric current to flow in the loop. This produces a magnetic field which varies in the same way as the speech or music signals being amplified. This magnetic field can be picked up on a tiny coil which may be installed inside a hearing aid or other special receiver. All the listener has to do to receive the amplified sound is to switch to the T or telecoil position on the hearing aid, press T on a remote control unit or use a special loop receiver with headphones.

最先出現的磁感應迴路通信系統是在1937年由Joseph Poliakoff在英國所發明的。「感應環迴」所運作的原理基本上與1937年的類似，但是在系統上有做更新與進化，像是在音響與電腦化(更科技化)的部分。The first patented magnetic induction loop communication system was invented by Joseph Poliakoff in Great Britain in 1937. “Hearing loops” work today for the same reasons today as in 1937 but the systems have evolved, just as audio engineering and computerization have.

在香港的普及程度:

• 大部分的政府建築都裝有感應環迴的系統。

• 政府建築推動「無障礙空間」(如:博物館、圖書館等等)。

• 在某些地方或是組織的機構(如:地鐵的電梯、香港迪士尼樂園、香港傷殘青年協會) 都設有感應環迴的系統(有T的圖示)。

在其他地方的普及度:

• 英國的火車上。

• 美國的一些教堂還有商店。

• 英國的一些醫院。

環線感應系統的可用性:

• 我們建議可以在工作場所、博物館、教堂、公車等等許多香港的地方安裝環線感應系統。在某些地方，特別是劇院、電影院和公眾禮堂，應在演出前播放廣播或是音樂到環線感應系統裡。這可以讓聽力受損的朋友們確認環線感應系統和自己的接收裝置是否正常運作。

難處:

• 安裝線圈的範圍。

• 在香港並不常見。比起國外，較少數的香港人知道「環線感應系統」這項科技。

Popularity in Hong Kong:

• Most of the governmental buildings has installed the loop system

• Governmental buildings promote “Barrier Free Facilities” (e.g. museum, library, etc.)

• In some places or organisations, for example MTR lift, Hong Kong Disney and HKFHY, there are loop systems with a "T "sign

Popularity in other places:

• In the trains in the UK

• In some churchs and shops in the United States

• In some hospitals in the UK.

Availability of loop systems:

• We suggest can install loop systems in work areas, museums, churches, buses and many more places still in Hong Kong. In some places, particularly in theatres, cinemas, and public halls, announcements or music should be played into the loop system prior to the commencement of the show. This enables hearing impaired people to check the operation of the loop and their own receiving devices.

Difficulties

• To install coil range

• Not common in Hong Kong. Less Hong Kong people know the knowledge of Loop system compared to foreign countries.