1.  Field of the Invention
The present invention deals with the field of devices for controlling exiting from a predefined area.  In particular the present invention is usable for restricting the removal of infants from predetermined areas such as the maternity ward of a hospital other than by fully authorized removal by specifically authorized personnel such as the parent of the child or specific health care workers. 
Personal security of infants within the maternity wards of hospitals or other similar areas has become a very dangerous problem for which hospitals are required to take appropriate security measures.  Many different types of alarm or emergency systems have been devised to prevent kidnapping of infants from maternity wards.  The present invention provides a novel advance in the apparatus and method for preventing such unauthorized removal of infants. 
2.  Description of the Prior Art
Many methods and apparatus have been devised for controlling and restricting the removal of newborn infants from maternity wards or other similar areas such as shown in U.S. Pat.  No.  3,016,056 patented Jan. 9, 1962 to J. B. Jacobs on a "Method Of Identifying Newly Born Infants"; and U.S. Pat.  No.  3,204,636 patented Sep. 7, 1965 to D. H. Kariher et al on a "Funis Clamp"; and U.S. Pat.  No.  3,247,852 patented Apr. 26, 1966 to J. D. Schneider and assigned to Hollister Incorporated on an "Umbilical Cord Clamp"; and U.S. Pat.  No.  3,292,080 patented Dec. 13, 1966 to E. M. Trikilis on a "System And Method For Preventing Pilferage By Detection Of Magnetic Fields"; and U.S. Pat.  No.  3,383,797 patented May 21, 1968 to E. M. Trikilis on a "Turnstile"; and U.S. Pat.  No.  3,418,613 patented Dec. 24, 1968 to E. M. Trikilis on a "Method Of Magnetizing A Large Quantity of Bulk Articles"; and U.S. Pat.  No.  3,524,225 patented Aug. 18, 1970 to E. M. Trikilis on a "Locking Assembly"; and U.S. Pat.  No.  4,212,303 patented Jul. 15, 1980 to J. Noland and assigned to Hollister Incorporated on an "Umbilical Cord Clamp"; and U.S. Pat.  No.  4,694,284 patented Sep. 15, 1987 to S. Leveille et al on an "Abduction-Preventing Collar"; and U.S. Pat.  No.  4,899,134 patented Feb. 6, 1990 to C. Wheeless, Jr. on a "Newborn Anti-Theft Device"; and U.S. Pat.  No.  4,973,944 patented Nov. 27, 1990 to G. Maletta on an "Electrical Signal And Alarm Protection Proximity Device"; and U.S. Pat.  No.  5,006,830 patented Apr. 9, 1991 to R. Merritt on a "Method And Device For Deterring The Unauthorized Removal Of A Newborn From A Defined Area"; and U.S. Pat.  No.  5,032,823 patented Jul. 16, 1991 to D. Bower et al and assigned to Digital Products Corporation on a "Secure Personnel Monitoring System" and U.S. Pat.  No.  5,047,750 patented Sep. 10, 1991 to L. Hector on a "Non-Intrusive Infant Security System".