| 发明名称 |
QUESTION*ANSWER SYSTEM FOR TV LECTURE |
| 摘要 |
PURPOSE:The up-and down-signal lines are provided between lecture room and classroom, and questioning equipment is installed at the lecture room side. In this way, question and answer can be carried out between lecture and classroom through signal lines. |
| 申请公布号 |
JPS52106223(A) |
申请公布日期 |
1977.09.06 |
| 申请号 |
JP19760022693 |
申请日期 |
1976.03.04 |
| 申请人 |
NIPPON TELEGRAPH & TELEPHONE |
发明人 |
IGAWA SHIROU;TAKAHASHI HIROSHI;AIZAWA KIYOSHI |
| 分类号 |
G09B5/08;G09B5/12;H04N7/15;H04N7/173 |
主分类号 |
G09B5/08 |
| 代理机构 |
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代理人 |
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