OMR scanners: reflective technology makes the difference.
Optical mark readers are experiencing a renaissance in both technology and application, or as one company explains, the technology "is evolutionary rather than revolutionary." This evolution refers to breakthroughs in OMR that make readers more efficient and less expensive.
* The Basics
OMR scanners were originally developed in the 1950s, with more desktop-sized models becoming available roughly 20 years later. The original technology, called "mark sensing," used a series of miniature sensing brushes to detect traces of graphite particles on a document as it passed through the machine. Now fiber optics similar to those used to read bar code symbols are employed.
One way to measure OMR efficiency is by the number of forms processed per hour.
The presence of a mark is detected by measuring the amount of light reflected from the surface of a form as it passes under a read head. The forms must be custom-designed, however any type of paper can be used since the mark is a surface entity; the thickness, color, weight and chemistry of the paper do not affect the reader's ability to determine if a mark is present.
The reading device contains an infrared light source and two sets of optical fibers. Light from one set is reflected off the form and picked up by the second set. In a stand-alone, grading environment, the presence of a mark in a particular position on the form is recorded and compared against a previously-scanned master. The reader usually acknowledges noncorresponding, "incorrect" marks by printing a mark on the form's border. Another use of OMR devices involves a computer and OMR software that recognizes the absence or presence of a mark in a particular position and translates that data into a computer file.
* Common Ground
Most optical mark readers have automatic feed hoppers that hold a certain amount of forms and do not require that an operator be present. Desktop models weigh between 30 and 40 pounds, interface to a computer via an RS232C serial port, and include a mark-density adjustment control.
One common way to measure the efficiency of an optical mark reader is by the number of forms it processes per hour. Two figures are often mentioned: the transport speed and the read speed. The transport speed refers to the maximum number of forms that can be fed through the machine per hour, while read speeds are the actual number of forms. The latter varies, as it is a function of the baud rate, number of timing marks and efficiency of the application program used.
New capabilities include being able to read ink marks on forms in addition to lead-generated marks, and to read two sides of a form simultaneously. All OMR scanners mentioned here offer the option of an ink-recognition head and a dual-read head.
* The Reader With Memory
The Model 8400 Optical Mark Reader from Scantron Corp. transports either 3,000 single-sided or double-sided forms per hour. The unit features a 500-sheet automatic document feeder and a 100-level darkness and discrimination technique that ignores poor erasures and smudges.
A built-in forms translator converts data into ASCII text records compatible with dBASE, Lotus 1-2-3, SPSS and Paradox applications programs. It weighs in at 40 pounds and the maximum form length accepted is 14 inches. The 8400 is capable of reading lead pencil and ink marks, as well as bar codes.
Descriptions are needed when more than one type of form will be used during one scanning period.
Either SCANFORM or SCANBOOK utility programs, which generate form-translation commands from user-defined form descriptions, is included with the reader. These descriptions are needed when more than one type of form will be used during one scanning period. Up to 99 descriptions, and therefore different form types, can be stored in the 8400's 128K memory. A second program, SCANEDIT, generates user-defined edit checks.
Kay Ratz, the director of computer services at the City of York School District located in York, Pa., uses the 8400 for testing and scoring purposes. Packets containing MAT6 standardized tests are sent to Ratz for processing. These double-sided answer sheets are scanned and the data files merged into a VAX computer system, comprised of a MicroVAX 3400 cluster, MicroVAX II and VAXstation 2000.
Each child's score is then compared against statistics describing the national norm scores for each grade level. This data is downloaded into the VAX system, which is networked to Macintosh computers at each school's site. With information online, administrators and instructors can generate a wide variety of custom reports in minutes. "Financially, it's is a big plus for us," Ratz explains. "The system will pay for itself in a very short while."
In addition, the turn-around period for graded MAT6 tests has decreased from five months to just two weeks--invaluable time that can be used to adjust curricula objectives to meet students' needs.
* 40-Character Display
National Computer Systems (NCS) has been employing OMR technology for the past 25 years. Their newest model, the OpScan 5, offers simultaneous data transfer between the scanner and a computer with a document throughput (transport) rate of 3,000 sheets per hour. The automatic-feed hopper holds 300 sheets to eliminate continual reloading and accommodates a variety of document sizes. The OpScan 5 boasts 16 levels of mark discrimination to differentiate between legitimate marks and erasures.
The reader is equipped with a 40-character, alpha-numeric display panel, which indicates the mode in use, operating instructions and other informative messages.
With a barcode attachment and ASCII-downloading capabilities, the unit is also compatible with NCS ScanTolls software. It also maintains and converts files into formats compatible with business-oriented software packages.
In Pasadena, Calif., Don Trigg uses the OpScan 5 to meet accountability reporting requirements for the Pasadena Unified School District. The district is using the optical mark reader to implement a program that will scan applications for free and reduced-priced breakfasts or lunches to immediately determine eligibility.
Another application involves using the unit for attendance tasks. Formerly on a key-punch system, the district switched to OMR technology in 1987, installing a scanner in each of its 32 schools. Now they use scannable sheets to generate attendance records, thus enabling Trigg to make projections and reports.
* Freedom of Forms
The HEI/380 optical mark reader from Scanning Systems transports 5,500 forms per hour and contains, as standard equipment, a dual-read head. Its automatic feeder is supported by 200-form input and 400-form output hoppers for forms as long as 17 inches. Additionally, the /380 comes with a one year warranty that the company may extend to two years.
Users can even print their own forms to lower overall scanning costs.
The /380 is identical to the company's HEI /360 model, which contains a single-read head. Neither unit discriminates between specific vendors' forms and Scanning Systems does not sell their own. This gives users the ability to choose from a variety of suppliers or even print their own forms, thus lowering their overall scanning costs.
In Palo Alto, Calif., Stanford University's Merrick Payton has been using a /360 model for the past three years and has recently purchased another. The university was using a very large, older scanner that relied on earlier OMR technology. It now uses the /360 in three areas, the most recent application being processing graduate admissions applications.
The three-page graduate application contains spaces for demographic and personal information, including name, address and social security number. Coding instructions are conveniently printed on the back of each form, taking advantage of the reader's reflective technology.
The final page of the form contains areas for applicants to mark in the graduate program, department and degree being applied for, his or her academic history, and all degrees previously conferred. "It's not a complicated application," says Payton, "but it takes away a good deal of key punch time." He adds that approximately 11,000 of these forms are scanned each year, creating a cost savings of $20,000 to $30,000 annually.
* On the Light Side
For smaller applications, Chatsworth Data Corp. manufactures the 9002, a lightweight (6 lbs.) OMR scanner that, despite its small size contains a dual-read and optional ink-recognition head at no extra cost. It requires manual feeding and sports a 40-form output hopper for the 1,000 forms-per-hour it scans. The maximum document length is 12 inches and all controls are software selectable.
* OMR on the Whole
On the whole, OMR is quite useful and far-reaching in its applications. Many colleges currently use OMR to process student course evaluation forms; scheduling media center materials is another possible application. These and many other tasks can be computerized with OMR to save districts and schools countless hours and budget dollars.
PHOTO : SERIAL PORT CONNECTS UNIT TO MICROS OR MAINFRAMES
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|Title Annotation:||includes directory of OMR vendors; Optical Mark Reader|
|Publication:||T H E Journal (Technological Horizons In Education)|
|Date:||Feb 1, 1991|
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