A proposed new federal law would impose criminal penalties on those who show explicit images on their Web sites unless a screening device is used to keep children from seeing them.\n The Senate bill, dubbed the Children's Online Protection Act, was introduced by Indiana Republican Daniel R. Coats. He said he wanted to be sure that children who inadvertently enter the wrong Web address won't get an eyeful of nudity and porn.The Senate version faced virtually no opposition as it went through the Senate Commerce Committee.\n The House version of the bill is sponsored by Rep. James C. Greenwood, a Pennsylvania Republican. He predicted the bill will gain favor with both moderate and conservative members of the GOP.\n If the bill is enacted, violators will faces fines of up to $50,000 and sentences of up to six months in jail. Web site operators who don't display explicit images until after an Internet user proves their age though a credit card or some other adult access code, would be exempt.\n The bill attempts to steer clear of the U.S. Supreme Court ruling which struck down most of the Communications Decency Act as an unconstitutional infringement on civil rights. Its backers believe that legislation is needed because software filters can be circumvented and Internet porn sites also benefit from random hits.\n The Children's Online Protection Act has some comapny in the halls of Congress. Another bill introduced in the Senate, the Internet School Filtering Act, would require that schools and libraries use software to block access to pornographic Web sites before getting any of the $2.5 billion in federal funds given to help schools and libraries connect to the Internet.\n That bill, offered by Sen. John McCain, an Arizona Republican, is opposed by the American Library Association, which argues that schools and libraries should make their own decisions regarding Internet access policies. A spokesman for the association said that professionals in schools may need access to sites that young children should not see and the same policies should not apply to both.\n An aide to Sen. McCain said acceptable use policies are too easily subverted.