Instead of having to do this or something similar to this ...

function (container, options) {
    $('<input data-text-field="' + options.field + '" ' +
            'class="k-input k-textbox" ' +
            'type="password" ' +
            'data-value-field="' + options.field + '" ' +
            'data-bind="value:' + options.field + '"/>')
            .appendTo(container)
}

add a type "password" to the grid and let the js do it without having to code :)