Product Name: Ly-220A (3D) LCD Vision Chart Model NO.: LY-220A(3D) Group: All Certification: CE Type: LCD Chart Monitor Classification: Optometry Equipment Product Name: Ly-220 LCD Vision Tester Series Electric Voltage: 220V/50Hz or 110V/60Hz Screen Size: 22 Inch Overall Size: 482*370*52mm Package: 52(L)X12(W)X41(H)Cm Trademark: VSO Transport Package: Standard Exporting Packaging Origin: Chongqing, China Product Description LY-220A LCD Visual ChartFeatures:1,Unique intelligent function: Customer uses direction keys on the controller to answer instrument according to his/her judgment of the optotypes randomly appeared on the screen, system automatically speaks out the best value of eyesight.2,Screen Brightness can be adjusted to be fit for the environment. The maximal screen brightness is 250cd/m2 according to national standard.3,Delicate design,high definition display: This instrument is designed with professional video and audio multimedia processing technology, with rapid response and convenient operation.4,With protecting function to ensure long lifespan of the screen.5,Compatible with multifold types of video and audio files.6,Accurate and exact, effective distance is 1-6m, can be adjusted to the minimum distance(1m) for crowded area.7,With the maximum 3 lines and 8 rows of optotypes showing on screen, convenient for test.8,Numerous option of optotypes: international C optotypes,E optotypes,letter optotypes,children optotypes,numeric optotypes,astigmatic optotypes,cross optotypes,binocular balance optotypes,color blindness optotypes, and so on. 3D-types instrument is designed with stereo polarization specially used for examine of stereo vision and binocular balance.9,Convenient and quick installation: simply hang or place on solid surface, easy to maintenance.10,LCD screen with the minimum 0.248mm of dot pitch and high resolution, vivid to display optotypes.11,Powerful extended function: instrument can be used as a computer display, or as a multimedia player with U disc.12,Allows to connect with AV or YPbPr signal. Specifications:Technical DataLY-185LY-215LY-220A LY-230(3D) Screen Size18.5''21.5''22"23"Packing Dimension52x 1 2x41cm60x13x45cm58.5x1 8x50cm68x1 2x45cmG.W.4.6kg5.3kg6.5kg5.6kg