G09B 3/085
With invisibly printed correct answer
Official title: {with invisibly printed correct answer; the answer being rendered visible by special optical means, e.g. filters; mirrors}
G09B3/085 (With invisibly printed correct answer) appears on 12 US grants and 2 published applications in this corpus.
Search patents in G09B- Granted patents
- 12
- Published applications
- 2
- Assignees
- 7
- Inventors
- 21
- Latest grant
- 31 May 2016
Filings by year
| Year | Granted patents | Published applications |
|---|---|---|
| 1976 | 1 | 0 |
| 1977 | 1 | 0 |
| 1978 | 1 | 0 |
| 1979 | 0 | 0 |
| 1980 | 1 | 0 |
| 1981 | 1 | 0 |
| 1982 | 1 | 0 |
| 1983 | 0 | 0 |
| 1984 | 0 | 0 |
| 1985 | 2 | 0 |
| 1986 | 0 | 0 |
| 1987 | 0 | 0 |
| 1988 | 1 | 0 |
| 1989 | 0 | 0 |
| 1990 | 0 | 0 |
| 1991 | 0 | 0 |
| 1992 | 0 | 0 |
| 1993 | 0 | 0 |
| 1994 | 0 | 0 |
| 1995 | 0 | 0 |
| 1996 | 0 | 0 |
| 1997 | 0 | 0 |
| 1998 | 0 | 0 |
| 1999 | 1 | 0 |
| 2000 | 0 | 0 |
| 2001 | 1 | 0 |
| 2002 | 0 | 0 |
| 2003 | 0 | 0 |
| 2004 | 0 | 0 |
| 2005 | 0 | 0 |
| 2006 | 0 | 1 |
| 2007 | 0 | 0 |
| 2008 | 0 | 0 |
| 2009 | 0 | 0 |
| 2010 | 0 | 0 |
| 2011 | 0 | 0 |
| 2012 | 0 | 0 |
| 2013 | 0 | 0 |
| 2014 | 0 | 0 |
| 2015 | 0 | 1 |
| 2016 | 1 | 0 |
By publication year. Applications have been published since 2001.
Recent patents
- Image processing apparatus and image processing method for appropriately processing and unnecessary text area or image area31 May 2016US 9,357,099 B2KYOCERA Document Solutions Inc.
- Method and apparatus for multiple choice testing system with immediate feedback for correctness of response3 Apr 2001US 6,210,171 B1
- Test booklet including tear out answer sheets having scratch-off answer selections20 Jul 1999US 5,924,740 AEnterprises for Continuing Education, Inc.
- Multicolor interactive notepad29 Nov 1988US 4,787,852 A
- Programmed learning textbook12 Nov 1985US 4,552,536 A
Most cited
By later US patents
- Apparatus for determining the result of answers to a set of related questions55US 4,213,251 ANational Research Development Corporation · 1980
- Optically scannable answer sheet booklet with sequence bars printed thereon and method of producing same14US 4,300,791 ANational Computer Systems, Inc. · 1981
- Xerographic method for making a responsive answer system9US 3,938,993 AXerox Corporation · 1976
- System for visual communication9US 4,084,332 A1978
- Multicolor interactive notepad9US 4,787,852 A1988