| # | Country | Total Patents | |
|---|---|---|---|
| #1 | France | 8 | |
| #2 | Germany | 3 | |
| #3 | United Kingdom | 1 |
| # | Industry | |
|---|---|---|
| #1 | Audio-visual technology | |
| #2 | Optics | |
| #3 | Electrical machinery and energy | |
| #4 | Measurement |
| # | Technology | |
|---|---|---|
| #1 | Loudspeakers and microphones | |
| #2 | Cameras | |
| #3 | Special information storage | |
| #4 | Television | |
| #5 | Electric motor controls | |
| #6 | Electric discharge tubes | |
| #7 | Measuring speed and acceleration |
| # | Name | Total Patents |
|---|---|---|
| #1 | Tigerstedt Eric Magnus Campbell | 5 |
| #2 | Tigerstedt Eric Magnus Campbel | 3 |
| Publication | Filing date | Title |
|---|---|---|
| GB167500A | Improvements in or relating to synchronism apparatus |