Abstract: Gray scale masks used to create optical elements are formed. Desired gray scale patterns may be created by varying a transmission across a mask, e.g., by varying the thickness of a light absorbing layer. Such variations in thickness may be created using multiple binary masks. Desired gray scale patterns may also be created on a computer using available software and then imaged onto film or a glass film plate. Direct contact or proximity printing is then used to transfer the true gray scale pattern onto a photoresist layer. The photoresist layer is then etched, thereby forming the desired pattern therein. All portions of the desired pattern are simultaneously formed in the photoresist layer. The etched photoresist layer is then used to photolithographically fabricate either the optical element itself or a master element to be used in injection molding or other replication techniques. The gray scale mask itself may be used repeatedly to generate photoresist layers.

Abstract: Gray scale masks used to create optical elements are formed. Desired gray scale patterns may be created by varying a transmission across a mask, e.g., by varying the thickness of a light absorbing layer. Such variations in thickness may be created using multiple binary masks. Desired gray scale patterns may also be created on a computer using available software and then imaged onto film or a glass film plate. Direct contact or proximity printing is then used to transfer the true gray scale pattern onto a photoresist layer. The photoresist layer is then etched, thereby forming the desired pattern therein. All portions of the desired pattern are simultaneously formed in the photoresist layer. The etched photoresist layer is then used to photolithographically fabricate either the optical element itself or a master element to be used in injection molding or other replication techniques. The gray scale mask itself may be used repeatedly to generate photoresist layers.

Abstract: Gray scale masks used to create optical elements are formed. Desired gray scale patterns may be created by varying the thickness of a light absorbing layer. Such variations in thickness may be created using multiple binary masks. Desired gray scale patterns may also be created on a computer using available software and then imaged onto film or a glass film plate. Direct contact or proximity printing is then used to transfer the true gray scale pattern onto a photoresist layer. The photoresist layer is then etched, thereby forming the desired pattern therein. All portions of the desired pattern are simultaneously formed in the photoresist layer. The etched photoresist layer is then used to photolithographically fabricate either the optical element itself or a master element to be used in injection molding or other replication techniques. The gray scale mask itself may be used repeatedly to generate photoresist layers.

Abstract: Gray scale masks used to create optical elements are formed. Desired gray scale patterns may be created by varying the thickness of a light absorbing layer. Such variations in thickness may be created using multiple binary masks. Desired gray scale patterns may also be created on a computer using available software and then imaged onto film or a glass film plate. Direct contact or proximity printing is then used to transfer the true gray scale pattern onto photoresist. The photoresist is then etched, thereby forming the desired pattern therein. All portions of the desired pattern are simultaneously formed in the photoresist. The etched photoresist is then used to photolithographically fabricate either the optical element itself or a master element to be used in injection molding or other replication techniques. The gray scale mask itself may be used repeatedly to generate photoresists. The imaging is particularly useful for forming optical elements having a plurality of arrays of refractive elements.

Abstract: A technique for aligning features on opposite surfaces of a substrate by generating a fiducial image at an image plane and identifying the location of the image at a viewing device remote therefrom, e.g., a video display screen. The substrate is placed so that one surface thereof, on which a feature is to be placed in alignment with a corresponding feature already present on the other oppositely disposed surface, is at the image plane. The one surface has photoresist material thereon. With the fiducial image turned off, an image of the feature on the other oppositely disposed surface is presented at the viewing device and the substrate is moved in the image plane until the image of the feature at the viewing device is at the previously identified location of the fiducial image.

Abstract: A device for aligning a flexible mask with a substrate when the substrate is mounted on a vacuum chuck member which includes a surround member surrounding the exposed surface of the substrate. The mask is held on a mask holder and the chuck member and mask holder are movable toward and away from each other. The surround member rests on a flexible element which effectively causes the surround member to float so that when the mask is brought into contact with the substrate, the mask always lies in the same plane as the exposed surface of the substrate and the exposed surface of the surround member and no distortion of the mask occurs.