browserName = navigator.appName;
version = "";
     browserVer = parseInt(navigator.appVersion);
             if (browserName == "Netscape" && browserVer >= 3) version = "n3";
             if (browserName == "Microsoft Internet Explorer" && browserVer >= 4) version = "n3";
             
             if (version == "n3")
             {

             but01_on = new Image( );
             but01_on.src = "img/btn_cr1.gif";
             but02_on = new Image( );
             but02_on.src = "img/btn_imager1.gif";
             but03_on = new Image( );
             but03_on.src = "img/btn_cassette1.gif";
             but04_on = new Image( );
             but04_on.src = "img/btn_jigenki1.gif";
             but05_on = new Image( );
             but05_on.src = "img/btn_drychem1.gif";
             but06_on = new Image( );
             but06_on.src = "img/btn_ip1.gif";
             but07_on = new Image( );
             but07_on.src = "img/btn_xsen1.gif";
             but08_on = new Image( );
             but08_on.src = "img/btn_film1.gif";
             but09_on = new Image( );
             but09_on.src = "img/btn_iyakuhin1.gif";
             but10_on = new Image( );
             but10_on.src = "img/btn_satsueidai1.gif";
             but11_on = new Image( );
             but11_on.src = "img/btn_ws1.gif";
             but12_on = new Image( );
             but12_on.src = "img/btn_vcr1.gif";
             but_home_on = new Image( );
             but_home_on.src = "img/home1.jpg";
             but_fms_on = new Image( );
             but_fms_on.src = "img/btn_fms1.gif";
             but_fsk_on = new Image( );
             but_fsk_on.src = "img/btn_fsk1.gif";
             but_dr_on = new Image( );
             but_dr_on.src = "img/btn_dr1.gif";
             but_dm_on = new Image( );
             but_dm_on.src = "img/btn_dm1.gif";
             but_ue_on = new Image( );
             but_ue_on.src = "img/btn_ue1.gif";


             but01_off = new Image( );
             but01_off.src = "img/btn_cr.gif";
             but02_off = new Image( );
             but02_off.src = "img/btn_imager.gif";
             but03_off = new Image( );
             but03_off.src = "img/btn_cassette.gif";
             but04_off = new Image( );
             but04_off.src = "img/btn_jigenki.gif";
             but05_off = new Image( );
             but05_off.src = "img/btn_drychem.gif";
             but06_off = new Image( );
             but06_off.src = "img/btn_ip.gif";
             but07_off = new Image( );
             but07_off.src = "img/btn_xsen.gif";
             but08_off = new Image( );
             but08_off.src = "img/btn_film.gif";
             but09_off = new Image( );
             but09_off.src = "img/btn_iyakuhin.gif";
             but10_off = new Image( );
             but10_off.src = "img/btn_satsueidai.gif";
             but11_off = new Image( );
             but11_off.src = "img/btn_ws.gif";
             but12_off = new Image( );
             but12_off.src = "img/btn_vcr.gif";
             but_home_off = new Image( );
             but_home_off.src = "img/home.jpg";
             but_fms_off = new Image( );
             but_fms_off.src = "img/btn_fms.gif";
             but_fsk_off = new Image( );
             but_fsk_off.src = "img/btn_fsk.gif";
             but_dr_off = new Image( );
             but_dr_off.src = "img/btn_dr.gif";
             but_dm_off = new Image( );
             but_dm_off.src = "img/btn_dm.gif";
             but_ue_off = new Image( );
             but_ue_off.src = "img/btn_ue.gif";
             }

     function img_on(imgName)
     {
             if (version == "n3") 
             {
             imgOn = eval(imgName + "_on.src");
             document [imgName].src = imgOn;
             }
     }

     function img_off(imgName)
     {
             if (version == "n3") 
             {
             imgOff = eval(imgName + "_off.src");
             document [imgName].src = imgOff;
             }
     }