An old engraving showing how a diaphragm mirror works. It is from Victorian book of the 1890s on sports, games and pastimes. Speech can be sent using light. A thin piece of glass or mica is at the end of the speaking tube. Speaking causes the diaphragm to vibrate, in a similar fashion to a telephone speaker plate. This causes the reflected beam of light to vary and distort. This can be picked up some distance from the mirror – a selenium cell, placed to pick up the light beam, can be used to convert these waves back into speech. However, it will only work over comparatively short distances.
An old engraving showing how a diaphragm mirror works. It is from Victorian book of the 1890s on sports, games and pastimes. Speech can be sent using light. A thin piece of glass or mica is at the end of the speaking tube. Speaking causes the diaphragm to vibrate, in a similar fashion to a telephone speaker plate. This causes the reflected beam of light to vary and distort. This can be picked up some distance from the mirror – a selenium cell, placed to pick up the light beam, can be used to convert these waves back into speech. However, it will only work over comparatively short distances.
Size: 3543px × 2782px
Location: UK
Photo credit: © M&N / Alamy / Afripics
License: Licensed
Model Released: No
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