LEA Test Intl, LLC™ is located in central Pennsylvania and responsible for all of Dr. Lea Hyvärinen’s trademarks, copyrighted works, and intellectual property to include LEA SYMBOLS®, LEA NUMBERS®, HIDING HEIDI®, LEA GRATINGS®, LEA 3-D PUZZLE®, LEA FLICKER WAND®, LEA RECTANGLES GAME®, and LEA MAILBOX GAME®.
Dr. Hyvärinen is a world-renowned Finnish ophthalmologist best known for the LH Vision Test System, now recognized as the LEA TEST VISION SYSTEM™. This system contains 40+ core tests for numerous clinical assessment situations in the vision screening of children and adults with different communication needs and cognitive levels. Her optotypes, (LEA SYMBOLS® and LEA NUMBERS®) are used in more than 150 other tests. The majority of these tests are produced by Good-Lite ® Company and distributed to 140+ countries.
NOTE: Among the pediatric visual acuity tests, the LEA SYMBOLS are the ONLY set of optotypes that have been calibrated with the Landolt C test and blur equally at threshold. In addition, the LEA NUMBERS are the ONLY set of numbers that has been calibrated with the Landolt C test, has even legibility, and blur equally.
In 1976, Dr. Hyvärinen designed the LEA SYMBOLS optotypes and had them calibrated against the Snellen E, the international reference optotype at that time. In 1977, the first LH tests were printed for testing at the Vision Rehabilitation Centre in Helsinki and then published in 1979 for distribution for Finnish health care centers. Dr. Hyvärinen first described her 4 symbols—apple, house, square, and circle—in a peer-reviewed journal in 1980. In 1988, the LEA SYMBOLS were calibrated against the Landolt C, the international reference optotype and replacement for the earlier Snellen E. The LH Symbols tests (now referred to as LEA SYMBOLS tests) are used for assessment of vision in children and became popular in the 1980’s for vision screening. In 1993, Dr. Hyvärinen created LEA NUMBERS for visual acuity tests at full and low contrast levels for international collaborative studies and in 1994 they were calibrated against the Landolt C.
The LEA TEST VISION SYSTEM includes the LEA SYMBOLS and LEA NUMBERS, and is the only complete vision testing system to use the same optotype across all testing situations. Dr. Hyvärinen's core tests are for screening and testing situations involving all children and can be used for conducting functional vision assessments in children and adults with developmental delays and disabilities. Dr. Hyvärinen's core tests assess near and distance visual acuity, contrast sensitivity, visual field deficits, cognitive vision, visual adaptation, and color vision. The American Academy of Pediatrics includes LEA SYMBOLS on its list of recommended tests for screening the vision of preschoolers.