From Forum Nokia Wiki

By using alert

public void splashScreen( 
                     Display d, Displayable next ){
    Image logo = null;
 
    try {
      logo = Image.createImage(
                              "/images/splashscreen.png" );
    }
    catch( IOException e ){
    }
 
    Alert a = new Alert( "SplashScreen", 
           "",
            logo, null ); 
    a.setTimeout( Alert.FOREVER );
    display.setCurrent( a, next );
}

For using Canvas http://java.sun.com/developer/J2METechTips/2001/tt0820.html#tip1