Abstract:
Embodiments of the invention provide patients with premium progressive lenses that are tailor-made to his or her specific and unique requirements and preferences. An interactive progressive lens optical design determining provides design technology that allows patients or eye care professionals to alter a progressive lens optical design in real-time, while continually displaying the selected lens&#39; optical performance, until the most suitable lens has been designed. The progressive lens optical design determining software mixes and blends a number of cornerstone designs in varying ratios to achieve the desired lens.

Description:
TECHNICAL FIELD 
       [0001]    Embodiments of the invention are directed, in general, to providing an interactive lens design system and, more particularly, to a system that allows real-time generation of progressive lens designs to more closely match a patient&#39;s needs. 
       BACKGROUND 
       [0002]    A progressive lens corrects sight for a range of viewing distances, which can be categorized as near, intermediate, and far. Near distance is associated with the need to see things close up, such as for reading, painting, or doing needlework. Intermediate distance is associated with the need to see things at about arm&#39;s length, such as for using a computer monitor, looking at a vehicle dashboard, or talking to others. Far distance is associated with the need to see things beyond arm&#39;s length, such as for driving, watching television, or playing sports. 
         [0003]    Progressive lenses are configured with each of these vision zones. The lens design may depend upon the wearer&#39;s particular needs or preferences and can be tailored to suit the wearer. In addition to providing lenses that can be used for all purposes, progressive lenses may also be designed for a specific task or “lifestyle.” For example, an “office” lens may not correct fully for far vision, but will work better than an all-purpose progressive lens for near and intermediate vision needs. Alternatively, a driving lens may not correct fully for near vision, but will work better than an all-purpose progressive lens for far and intermediate vision needs. 
         [0004]    All progressive lenses have some unusable areas in which the vision through these areas is distorted. “Harder” designs have larger areas of useful vision, smaller areas of distorted vision, and a faster transition between the two areas. “Softer” designs have smaller areas of useful vision, larger areas of distorted vision, and a slower transition between the two areas. The peak distortion is lower in a softer design, which is usually more comfortable for most wearers. 
         [0005]    Existing progressive lens systems offer a set number of progressive lens design choices to users. For example, ten progressive lens designs might be offered and the wearer is limited to selecting only from that set of designs. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    Having thus described the invention in general terms, reference will now be made to the accompanying drawings, wherein: 
           [0007]      FIG. 1  is a flowchart illustrating an overview of a process for using the progressive lens design system according to one embodiment. 
           [0008]      FIG. 2  illustrates a progressive lens zone-tailoring interface according to one embodiment. 
           [0009]      FIG. 3  illustrates a zone-tailoring interface for progressive lens design when a user has selected an all-purpose progressive lens design and indicated that he or she currently uses progressive lenses. 
           [0010]      FIG. 4  illustrates a zone-tailoring interface for progressive lens design when a user has selected an all-purpose progressive lens design and indicated that he or she currently uses single-vision lenses. 
           [0011]      FIG. 5  illustrates a zone-tailoring interface for progressive lens design when a user has selected an office lens design and indicated that he or she currently uses bifocal lenses. 
           [0012]      FIG. 6  illustrates a zone-tailoring interface for progressive lens design when a user has selected a driving lens design and indicated that he or she currently uses bifocal lenses. 
           [0013]      FIG. 7  illustrates a zone-tailoring interface for progressive lens design when a user has selected a sports lens design and indicated that he or she currently uses bifocal lenses. 
           [0014]      FIG. 8  illustrates a display shown to a user based upon his or her initial progressive lens design using the parameters selected in the zone-tailoring section. 
           [0015]      FIG. 9  illustrates a display that corresponds to modified progressive lens display. 
           [0016]      FIG. 10  is an alternative embodiment of an interface for fine tuning of the progressive lens design options generated in the zone tailoring phase. 
           [0017]      FIG. 11  illustrates another method for modifying a progressive lens design. 
           [0018]      FIG. 12  illustrates four example cornerstone progressive lens designs. 
           [0019]      FIG. 13  is a flowchart illustrating a process for operating a progressive lens design system according to one embodiment. 
       
    
    
     SUMMARY 
       [0020]    The invention relates to a method implemented by computer means for determining a progressive lens optical design suitable for specific user&#39;s need, comprising: 
         [0021]    i) receiving user inputs in a zone-tailoring phase; 
         [0022]    ii) determining an initial progressive lens optical design based upon the zone-tailoring phase inputs; 
         [0023]    iii) displaying the initial progressive lens optical design and two boundary progressive lens optical designs to the user; 
         [0024]    iv) receiving inputs indicating that the modified progressive lens optical design should be closer to one of the boundary designs and one or more additional user inputs in a fine-tuning phase; 
         [0025]    v) modifying the initial progressive lens optical design based upon the inputs indicating that the modified progressive lens optical design should be closer to one of the boundary designs and based upon the fine-tuning phase inputs to determine a modified progressive lens optical design; 
         [0026]    vi) displaying the modified progressive lens optical design to the user; 
         [0027]    vii) receiving an indication regarding whether additional modifications to the optical design are needed by the user; 
         [0028]    viii) in response to the received indication being indicative of additional modifications to the optical design are needed by the user, repeating steps iv) to vii); and 
         [0029]    ix) in response to the received indication being indicative of no additional modifications being needed, determining data representative of a final progressive lens optical design from the modified progressive lens optical design. 
         [0030]    According to further embodiments which can be considered alone in any possible combination:
       the method further comprises manufacturing a progressive lens at a lens manufacturing side, based at least on the data representative of the final progressive lens optical design; wherein the displaying according to step iii) and step vi) are done at a lens ordering side; and wherein the modifying according to steps i) and v) is done at a lens determining side; and/or   the zone-tailoring phase comprises:
           receiving user inputs indicating an intended use of the progressive lenses; and   receiving user inputs indicating a current lens type worn by the user; and/or   
           the determination of the initial progressive lens optical design according to step ii) is determined based on a weighted combination of a plurality of pre-existing cornerstone progressive lens optical designs and wherein modifying the progressive lens optical design according to step v) implies a further modification of said weighted combination based on the one or more additional user inputs; and/or   displaying the initial progressive lens optical design to the user further comprises:
           generating a blurred image from the initial progressive lens optical design; and   overlaying the blurred image on an image of a real-world scene; and/or   
           the real-world scene is selected by the user; and/or   the method further comprises:
           generating an updated blurred image from the modified progressive lens optical design; and   overlaying the updated blurred image on the image of the real-world scene; and/or   
           the fine-tuning phase comprises receiving user inputs indicating changes in a boundary between distorted and clear areas in the initial progressive lens optical design; and/or   the fine-tuning phase comprises in response to the received indication being indicative of additional modifications to the optical design are needed by the user, repeating steps i) to vii).       
 
         [0045]    The invention further relates to a system for determining a progressive lens optical design comprising:
       at a lens ordering side, user&#39;s input collecting means to collect user&#39;s input related to zone tailoring and/or user&#39;s input indicating that a modified progressive lens optical design should be closer to one of two boundary designs and/or one or more additional user&#39;s input and/or indication regarding whether additional modifications to the optical design are needed by the user;   at a lens determining side, lens optical design determining means configured to:
           receive user&#39;s input from lens ordering side, user&#39;s inputs being related to zone tailoring and/or indicating that a modified progressive lens optical design should be closer to one of the two boundary designs and/or one or more additional user&#39;s input;   determine an initial progressive lens optical design based at least upon user&#39;s input related to the zone tailoring;   determine a modified progressive lens optical design based on the user&#39;s input indicating that the modified progressive lens optical design should be closer to one of the two boundary designs and/or based on the one or more additional user&#39;s input; and   send to lens ordering side, data representative of the initial progressive lens optical design and/or of the modified progressive lens optical design; and   
           at a lens ordering side, progressive lens optical design display means configured to display the initial progressive lens optical design, and/or the two boundary progressive lens optical designs, and/or the modified progressive lens optical design.       
 
         [0053]    According to further embodiments which can be considered alone in any possible combination:
       the system further comprises a database configured to store pre-existing corner stone progressive lens optical designs, the database being connected to the optical design determining means and wherein the lens optical design determining means are further configured to determine the initial progressive lens optical design and/or the modified progressive lens optical design based on a weighted combination of a plurality of said pre-existing cornerstone progressive lens optical designs; and/or   the zone-tailoring input comprises data representative of the relative importance of a plurality of progressive lens zone and/or data representative of the softness of a progressive lens optical design; and/or   the progressive lens optical design display means is further configured to display a blurred image based upon an initial progressive lens optical design, wherein the blurred image indicates clear and distorted areas on an image of a real-world scene.       
 
         [0057]    Embodiments of the invention provide patients with premium progressive lenses that are tailor-made to the user&#39;s specific and unique requirements and preferences. An interactive progressive lens optical design determining system provides progressive lens optical design determining technology that allows patients (or eye care professional, optician, etc.) to alter a progressive lens optical design in real-time, while continually displaying the selected lens&#39; optical performance, until the most suitable lens optical design has been determined. The wording “optical design” is a widely used wording known by a man skilled in the art in ophthalmic domain to designate the set of data indicative of a dioptric function of an ophthalmic lens. The wording “dioptric function” corresponds to the optical lens power (mean power, astigmatism, etc.) as a function of the gaze direction. Each ophthalmic progressive lens can be provided with a specific “optical design” depending on a specific user&#39;s need so as to restore a presbyope&#39;s ability to see clearly at all distances but also to optimally respect physiological visual functions such as foveal vision, extra-foveal vision, binocular vision and to minimize unwanted astigmatisms. For example but not limited to, a progressive lens “optical design” data may comprise data indicative of power profile along the main gaze directions (meridian line) used by the lens wearer during day life activities, and distributions of powers (mean power, astigmatism, etc.) on the sides of the lens, that is to say away from the main gaze direction. 
         [0058]    In various embodiments, displaying the selected lens&#39; optical design includes displaying or presenting simulated optical effects (including but not limited to dioptric effects) generated by the lens optical design to the patient in real-time, as the progressive optical design is altered. The progressive lens optical design determining system mixes or blends a number of pre-existing cornerstone optical designs in whatever varying ratios are required to determine the desired progressive lens optical design. This allows the patient to select, for example, an all-purpose progressive optical design, a lifestyle-specific progressive optical design, or an optical design that mixes features of both optical design types. The patient can then experience a display of simulated optical effects (including but not limited to dioptric effects) of the determined desired progressive lens optical design. 
         [0059]    Information will be gathered at a lens ordering side from the patient using, for example, zone tailoring that will allow the progressive lens optical design determining system to offer appropriate designs to each patient. In various embodiments, the lens ordering side may be located at an office of an eye care professional, a kiosk, a user&#39;s home, or anywhere the patient can be presented with an interface to the progressive lens optical design system. The progressive lens optical design determining system demonstrates the performance of a progressive lens optical design to the patient by displaying a real-life view modified by the lens&#39;s optical properties. As described previously, the real-life view changes as the patient fine-tunes the progressive lens optical design during the interactive process. 
         [0060]    The patient is first presented with simulated optical effects (including dioptric effects) of a proposed progressive lens optical design along with two other simulated optical effects of lens optical design options. The two lens optical design options are representative of limits to the possible range of lens optical design modifications. In various embodiments, the proposed progressive lens optical design initially represents a lens optical design that is midway between the two lens optical design options. If the patient is satisfied with the midway lens optical design presented initially, no further modification would be necessary. However, if desired, the patent can incrementally change the design part of the way, or fully, towards either of the design options. The patient can cause the system to modify the proposed progressive lens optical design by modifying interactively the boundaries of the proposed progressive lens optical design towards one of the lens optical design options until the desired result is achieved. The interactive modification of the progressive lens optical design can be done, for example, using touch screen technology, physical, or other graphical input means as described in greater detail below. 
         [0061]    Embodiments of the invention provide the ability to mathematically combine and blend a number of pre-existing cornerstone progressive lens optical designs in any desired ratio. The ratio of each design used in the blending process depends upon a patient&#39;s visual needs. The progressive lens optical design determining system allows the patient, in conjunction with his or her eye care professional, to have a very large selection of optical designs and optical-performance choices for the various zones of the progressive-lens. This allows the patient and/or eye care professional to determine, for example, in real-time, a progressive lens optical design that best matches the patient&#39;s requirements. In various embodiments a patient may determine his preferred lens optical design without the assistance of his eye care professional by using a personal computer at their home, from a remote kiosk, or any number of other possible locations of the lens ordering side. In various embodiments, the lens ordering side may be located remotely, but in communication with a lens determining side. In other embodiments, the lens determining side is co-located with the lens ordering side. Regardless of its location, the lens determining side is responsible for receiving information from the lens ordering side and processing the received information to modify and determine the progressive optical lens design the patient desires. 
       DETAILED DESCRIPTION 
       [0062]    The invention now will be described more fully hereinafter with reference to the accompanying drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. One skilled in the art may be able to use the various embodiments of the invention. 
         [0063]    In one embodiment, a progressive lens optical design determining system allows a user, such as a patient, eyeglasses customer, or eye care professional, to interactively determine a progressive lens optical design. Initially, at the lens ordering side, the progressive lens optical design determining system accepts the user&#39;s eyeglasses prescription, measurements for a desired frame, and the patient&#39;s physical measurements. The user then enters the patient&#39;s needs for the progressive lens to be determined. For example, the user may indicate the relative importance of the far, intermediate, and near regions of the progressive lens optical design as well as a desired relative “softness” of the optical design. This allows for the determination, at the lens determining side, of a progressive lens optical design that is specifically tailored to the individual user. As described previously, the lens ordering side and the lens determining side may be located apart from each other in various embodiments and may be co-located in other embodiments. 
         [0064]    The progressive lens optical design determining system may provide an initial starting point or suggested progressive lens optical design based upon the user&#39;s inputs, such as the user&#39;s occupation, hobbies, or likely use of the progressive lens eyeglasses. The user then modifies the initial proposed lens optical design (e.g., by adjusting the relative importance of the far, intermediate, or near regions and the softness of the design) to determine a progressive lens optical design having the specific characteristics desired by the user. The progressive lens optical design determining system will determine, at the lens determining side, the best lens optical design based on the information provided by the user and display, at the lens ordering side, simulated optical effects of the lens optical design to the user, before the progressive lens is ever physically manufactured. This allows the user to tailor a lens to suit particular needs or preferences. For example, the user may determine a progressive lens optical design based upon his everyday life and the tasks that he needs eyeglasses to perform. The system may be used to determine progressive lens optical designs for a specific task or lifestyle as well as progressive lens optical designs for general use. 
         [0065]    In one embodiment, the system uses pre-existing cornerstone optical designs that can be stored remotely and accessed over a network by the progressive lens optical design determining system. Remotely storing the pre-existing cornerstone optical designs allows the optical designs to be stored in a central database and managed from a single location. In other embodiments, the pre-existing cornerstone optical designs are stored locally, or in any combination of local and remote storage. A number of these pre-existing cornerstone optical designs can be individually weighted and combined to generate a specific progressive lens optical design corresponding to user&#39;s needs. It is important to note that rather than using only objective criteria, the system also considers subjective feedback from the user into determining the lens optical design. Once the relevant weight and combination of the pre-existing cornerstone optical designs is calculated and the desired progressive lens optical design has been determined, the data representative of the desired progressive lens optical design may be sent to a lens manufacturing side to manufacture a progressive lens incorporating said desired progressive lens optical design. A lens manufacturing side may be located anywhere in which the capability to manufacture lens from the data representative of the desired progressive lens optical design exists. For example, the lens manufacturing side may be located at a traditional optical laboratory, at an office of an eye care professional, a kiosk, a residence, or any number of other locations. 
         [0066]      FIG. 1  is a flowchart illustrating an overview of a process for using the progressive lens optical design determining system according to one embodiment. In step  101 , the user provides input regarding his needs and expected use of the progressive lens. For example, the user inputs may identify a need for an office lens that does not correct fully for far vision, but that is better than an all-purpose progressive for near and intermediate vision. Alternatively, the user inputs may identify a need for a driving lens that does not correct fully for near vision, but that is better than an all-purpose progressive for far and intermediate vision. 
         [0067]    The user&#39;s input may be collected, for example, using a zone-tailoring interface to gather information that will allow the progressive lens optical design software to offer appropriate designs. In other embodiments, a questionnaire or survey may be used to collect user input regarding a desired progressive lens optical design. The information provided via the zone-tailoring interface or collected in a questionnaire or survey allows the system to determine how to prioritize the different progressive lens zones for each particular user. 
         [0068]    In step  102 , the system determines an initial progressive lens optical design based upon the user inputs in the zone-tailoring interface. The system determines the initial lens optical design as a weighted sum of a plurality of cornerstone designs based at least upon user input entered in the zone-tailoring phase. For example, the initial lens optical design may be adapted for all purpose, office use, or driving use as indicated by the user. Depending on the type of lens the patient requests, default settings for the progressive lens zones are offered in the initial lens optical design. In step  103 , the system displays the initial lens optical design to the user in a “through the lens” scene that illustrates the clear and distorted areas in the lens optical design. 
         [0069]    In step  104 , the user may provide additional input to modify the current lens optical design. For example, the user may change the relative importance of the far, intermediate, and near zones or the softness of the progressive lens optical design. In step  105 , the system determines a revised progressive lens optical design based upon the user&#39;s modifications. The revised progressive lens optical design is generated by recalculating the plurality of weighted cornerstone designs to achieve the layout of the zones corresponding to the user&#39;s revised inputs. As described previously, the revised lens optical design is determined at the lens determining side, which may be located remotely or co-located with the lens ordering side. 
         [0070]    In step  106 , the system displays the revised lens optical design to the user in a through-the-lens scene that illustrates the clear and distorted areas in the modified design. In step  107 , the system determines whether the user is satisfied with the current lens optical design. If not, then the process returns to step  104  and the user continues to modify the lens optical design by providing additional inputs. 
         [0071]    Once the user is satisfied with the current lens optical design at step  107 , then the user selects that final optical lens design in step  108 . In step  109 , the final lens design is sent to a lens manufacturing side to be manufactured. The lens manufacturing side can be any location, such as an optical laboratory where the lens can be manufactured. In other embodiments, the lens manufacturing side is located in the office of an eye care professional, in a kiosk, a residence, or any other location capable of manufacturing the lens. In various embodiments, the final lens design is sent to the lens manufacturing side in the form of an order. The order includes at least the relevant information required by the laboratory to manufacture the final lens optical design. 
         [0072]      FIG. 2  illustrates a progressive lens zone-tailoring interface  200  according to one embodiment. Area  201  indicates the relative importance of the progressive lens zones and the softness of the progressive lens optical design. Segments  202 ,  203 ,  204  represent the relative importance of each of the far, intermediate and near vision zones, respectively. The horizontal shading across area  201  indicates the relative softness of the progressive lens optical design. As illustrated in  FIG. 2 , shaded areas  211 ,  213  are much darker than area  212 , which indicates in this example a “less soft” progressive lens optical design. In other embodiments, the horizontal shading of area  201  may be softer, smoother, or less distinct to indicate a “softer” progressive lens zones. 
         [0073]    The user provides his initial input regarding desired use (buttons  220 - 223 ) and current lens type (buttons  217 - 219 ). Buttons  220 - 223  allow the user to quickly select particular initial progressive lens optical designs based upon an expected use, lifestyle, hobby, etc. Button  220  allows the user to indicate that he wants an all-purpose progressive lens optical design. The distribution of segments  202 - 204  in  FIG. 2  illustrates one embodiment of an initial all-purpose progressive lens optical design. Button  221  allows the user to indicate that he wants a progressive lens optical design primarily for office use. Button  222  allows the user to indicate that he wants a progressive lens optical design primarily for driving. Button  223  allows the user to indicate that he wants a progressive lens optical design primarily for sports. 
         [0074]    Section  216  allows users to input a current lens type. This information may be used to select the initial progressive lens optical design softness for the user. Depending on what type of lenses the patient currently wears, a default softness of the lens optical design is offered to the user. This softness may then be modified by the user. For example, if the user selects button  217  to indicate that he is currently using bifocal lenses, the system may select an initial lens optical design that has a hard progressive lens optical design. The user may alternatively indicate that he is currently using a single vision lens with button  218 , which may trigger a softer progressive lens optical design. Button  219  may be used to indicate that the user is currently using a progressive lens, which may indicate that some middle range of softness should be used for the lens optical design. 
         [0075]    Based upon the user&#39;s initial inputs (buttons  220 - 223  and buttons  217 - 219 ), the system then displays an initial representation of, or a simulated optical effect generated by, the lens optical design of a progressive lens in area  201 . The user may further modify the initial representation, such as by adjusting the relative importance of the near, intermediate, and far vision zones (using buttons  205 ,  206 ,  208  and  209 ) and by adjusting the softness of the progressive lens optical design (using buttons  214 ,  215 ). Changes to the initial progressive lens optical design can be, for example, indicated by changes in the segments&#39; sizes and shading in area  201 . 
         [0076]    Buttons  205 ,  206  allow the user to adjust the relative importance  207  between the far vision zone and intermediate vision zone as indicated by the boundaries  207 ,  210  between segments. Button  205  moves boundary  207  up (i.e., decreases the importance of far vision zone  202  and increases the importance of intermediate vision zone  203 ), and button  206  moves boundary  207  down (i.e., increases the importance of far vision zone  202  and decreases the importance of intermediate vision zone  203 ). Similarly, buttons  208 ,  209  allow the user to adjust the boundary  210  between the intermediate vision and near vision zone. Button  208  moves boundary  210  up (i.e., decreases the importance of intermediate vision zone  203  and increases the importance of near vision zone  204 ), and button  209  moves boundary  210  down (i.e., increases the importance of intermediate vision zone  203  and decreases the importance of near vision zone  204 ). 
         [0077]    Buttons  214 ,  215  allow the user to adjust the softness of the progressive lens optical design. Button  214  is used to indicate that the user wants a harder lens optical design, and button  215  is used to indicate that the user wants a softer lens optical design. It will be understood that in other embodiments, the lens optical design may be defined in terms of “hardness” instead of “softness.” 
         [0078]      FIG. 3  illustrates a zone-tailoring interface  300  for progressive lens optical design when the user has selected an all-purpose progressive lens optical design (button  220 ) and indicated that he currently uses progressive lenses (button  219 ). Area  301  includes segments  202 ,  203 ,  204  to represent the relative importance of the far vision zone, intermediate vision zone and near vision zone, respectively, for the all-purpose progressive lens optical design. The horizontal shading  302  of area  301  indicates a medium softness of the progressive lens vision zones. 
         [0079]      FIG. 4  illustrates a zone-tailoring interface  400  for progressive lens optical design when the user has selected an all-purpose progressive lens optical design (button  220 ) and indicated that he currently uses single-vision lenses (button  218 ). Area  401  includes segments  202 ,  203 ,  204  to represent the relative importance of the far vision zone intermediate vision zone and near vision zone, respectively, for the all-purpose progressive lens optical design. The horizontal shading  402  of area  401  indicates a relatively softer progressive lens optical design. 
         [0080]      FIG. 5  illustrates a zone-tailoring interface  500  for progressive lens optical design when the user has selected an office lens design (button  221 ) and indicated that he currently uses bifocal lenses (button  217 ). Button  221  allows the user to indicate that he wants an office progressive lens optical design (i.e., one that is more heavily weighted, for example, for near vision and intermediate vision), such as when he wants to ensure good vision at a desktop and computer screen distances. Area  501  indicates the relative importance of the progressive lens vision zones and the softness of the lens optical design for the initial office lens. Segments  502 ,  503 ,  504  represent the relative importance of the far vision zone, intermediate vision zone and near vision zone, respectively, which are heavily weighted in the near and intermediate vision zones. 
         [0081]      FIG. 6  illustrates a zone-tailoring interface  600  for progressive lens optical design when the user has selected a driving lens design (button  222 ) and indicated that he currently uses bifocal lenses (button  217 ). Button  222  allows the user to indicate that he wants a driving progressive lens optical design (i.e., one that is more heavily weighted for intermediate vision and far vision), such as when he wants to ensure good vision at a dashboard and road/highway distances. Area  601  indicates the relative importance of the progressive lens vision zones and the softness of the lens optical design for the initial office lens. Segments  602 ,  603 ,  604  represent the relative importance of the far vision zone, intermediate vision zone and near vision zone, respectively, which are heavily weighted in the intermediate and far vision zones. 
         [0082]      FIG. 7  illustrates a zone-tailoring interface  700  for progressive lens optical design when the user has selected a sports lens design (button  223 ) and indicated that he currently uses bifocal lenses (button  217 ). Button  223  allows the user to indicate that he wants a progressive lens optical design that is more heavily weighted for far vision, such as when he wants to ensure good vision of other players, balls, goals, etc. Area  701  indicates the relative importance of the progressive lens zones and the softness of the lens optical design for the initial office lens. Segments  702 ,  703 ,  704  represent the relative importance of the far vision zone, intermediate vision zone and near vision zone, respectively, which are heavily weighted in the intermediate and far vision zones. 
         [0083]    After zone tailoring using the interface illustrated in  FIGS. 2-7 , the progressive lens optical design determining system moves to a fine tuning phase. First, an initial progressive lens optical design is designed based on the parameters selected in the zone tailoring section. Then, the system allows the user to modify the initial lens optical design with a controlled amount of variation. The initial progressive lens optical design is displayed to the user by presenting a picture, or simulated image, depicting what would be seen through the currently selected progressive lens optical design. 
         [0084]      FIG. 8  illustrates a display  800  that is shown to the user based upon his initial progressive lens optical design using the parameters selected in the zone-tailoring section. In various embodiments, the display may be presented on a tablet computer, a computer monitor, a television monitor, or any other device enabled to accurately present a simulated optical effect generated by the lens optical design to a user, for example, a head mounted device. A main area  801  shows a “real-life” view  802  through the initial lens optical design. A scene having a far vision area  803  and a near vision area  804  is shown as if viewed through the lens area  802 . An intermediate transition area  805  is also shown. The display also shows the shape of the clear  806  and distorted  807  areas on the progressive lens optical design. 
         [0085]    Display  800  also shows thumbnail views  808 ,  809 , which indicate modifications that can be made to the initial progressive lens optical design represented in main area  801 . For example, thumbnail views  808 ,  809  indicate changes in the shape of the clear and distorted areas compared to the main view  801 . The main view  801  represents a mix of the lens optical designs shown in the thumbnail views  808 ,  809 . Bars  810 ,  811  indicate the proportion of each thumbnail design  808 ,  809  that is shown in main area  801 . For example, in  FIG. 8 , the progressive lens optical design represented in main area  801  is a combination of half of each thumbnail design. 
         [0086]    The user can modify the initial progressive lens optical design shown in main area  801  by selecting either thumbnail design  808 ,  809 . For example, the user may point to and “click” on one of the thumbnail pictures using a pointing device ( 812 ) that is controlled using a mouse, track pad, touch screen, or similar device. The user may click on the desired thumbnail view to cause the main view  801  to gradually change toward the lens optical design illustrated in the thumbnail view. 
         [0087]      FIG. 9  illustrates a display  900  that corresponds to display  800  ( FIG. 8 ) after thumbnail  808  has been selected a number of times. The initial progressive lens optical design has been slightly modified toward the lens optical design represented in thumbnail  808 . Main area  801  shows the view  802  through the modified lens optical design. The display shows how the shape of the clear  901  and distorted  902  areas on the progressive lens optical design have changed relative to display  800 . Bars  903  and  904  have also changed to indicate that the view shown in main area  801  represents a higher proportion (e.g., 80-85%) of the thumbnail  808  design and a lower proportion (e.g., 15-20%) of the thumbnail  809  design. 
         [0088]    Once the user has finished fine tuning the progressive lens and the lens optical design has been finalized, the system then outputs a file that contains sufficient information to be used by software on the lens manufacturing side to manufacture the desired progressive lenses. The file may then be transmitted along with, or as an order for the patient to the lens manufacturing side, configured to accept the file for manufacturing progressive lenses. In various embodiments, the file is stored remotely, such as in a central database, and can be accessed by lens manufacturing side upon receiving an order indicating where to access the file with the progressive lens optical design information. 
         [0089]      FIG. 10  is an alternative embodiment of an interface  1000  for fine tuning of the progressive lens optical design options generated in the zone tailoring phase. In interface  1000 , instead of displaying a midpoint of two lens optical design boundaries, the user is presented with thumbnail images  1001 ,  1002  of two boundary lens optical designs that were generated from the zone tailoring information. The user selects either of these boundary lens optical design options  1001 ,  1002 , for example, by clicking with a pointing device  1003 . The selected boundary lens optical design is then provided in main viewing area  1004 . The user may then further modify the selected lens optical design in main viewing area  1004 . 
         [0090]    The user may make modifications to selected progressive lens optical design represented in the main viewing area  1004  using any appropriate technique available on the progressive lens optical design determining system. For example, as illustrated above in  FIGS. 8 and 9 , the user may select (e.g., point and click) on an input associated with a boundary lens optical design limit to incrementally move the current progressive lens optical design shown in the main viewing area  1004  toward the selected design. In other embodiments, the user may modify the shape of the clear ( 1005 ) and distorted ( 1106 ) areas, such as by “dragging-and-dropping” the boundaries ( 1007 ) between those areas. 
         [0091]      FIG. 11  illustrates another method for modifying a progressive lens optical design. Touch-sensitive or touchscreen display  1100  includes a main area  1101  that shows a real-world view through an initial lens design. In this embodiment, the user may modify the shape of the clear ( 1102 ) and distorted ( 1103 ) areas by moving boundary  1104  using his fingers, such as by pinching, swiping, tapping, or using any other acceptable input to touchscreen  1100 . 
         [0092]    Additionally, the system has the ability to translate a contour plot into a blur mask that can be overlaid on any “real-world scene” the user chooses. The system can store a range of “real-world scenes” to best demonstrate the properties of the progressive lens optical design. For example, instead of the daytime, outdoor phone-and-park scene shown in  FIGS. 8-11 , the user may choose to view the progressive lens optical design with a scene having any lighting or environmental conditions (e.g., computer and office, map and road junction, or dinner table) that best reflect where the user anticipates wearing the progressive lens. 
         [0093]    Embodiments of the invention combine two or more cornerstone progressive lens optical designs to create the user-selected final lens optical design. For example, a progressive lens optical design with a very wide reading area may be mixed with a progressive lens optical design having a very small reading area in a 1:1 ratio to determine a progressive lens optical design in which the reading area has a medium size. Expanding on this concept, the progressive lens optical design determining system uses a range of boundary designs and controls the ratio in which selected ones of these designs are mixed. This gives the system the ability to produce an infinite number of variations of progressive lens optical design with whatever optical properties the user requires. 
         [0094]    It will be understood that the user interfaces and displays illustrated in  FIGS. 2-11  are representations of certain examples and are not intended to limit how a user may operate and interact with a progressive lens optical design determining system. As described previously, the interfaces illustrated in  FIGS. 2-11  may be displayed to a user using, for example, the display on a desktop, laptop, notebook, or tablet computer, a workstation, an Internet web page, a kiosk, and the like. The progressive lens optical design determining system may allow the user to input lens information using, for example, a keyboard, number pad, pointing device (e.g, a mouse, touchpad, track pad, etc.), bar code reader, specific-use buttons, switches, or sliders, touch-sensitive display screen, or any other appropriate device. Additionally, the progressive lens optical design determining system includes a processing means at a lens determining side. The processing means is configured at least to modify, determine, and receive progressive lens optical designs. In various embodiments, the progressive lens optical design determining system additionally includes a database or other storage for storing corner stone designs used in the system. 
         [0095]      FIG. 12  illustrates four example cornerstone progressive lens optical designs  1201 - 1204  having preselected characteristics. Each design  1201 - 1204  is configured for a different combination of transitions between the reading (near) and distance vision zones of a progressive lens. The darker the area within the design indicates more distortion. 
         [0096]    Based on the user&#39;s inputs (zone tailoring), a weighted combination of these cornerstone designs may be used to generate an initial progressive lens optical design for consideration by the user. The user may then further adjust (fine tuning) the initial design to achieve a desired final progressive lens optical design. The zone tailoring inputs may provide an initial weighting for selected cornerstone designs, and the fine tuning inputs further revise that weighting. 
         [0097]    For example, if a user indicates that he wants a progressive lens with medium distance and medium reading vision zones, then the system may combine cornerstone designs  1201  and  1202  with an equal weighting or in a 1:1 ratio to generate an initial design. That initial design is displayed to the user with a scene showing a real-world view through the lens. The user then fine tunes the progressive lens optical design as indicated above. If, for example, the user selected a harder lens optical design during the fine tuning phase, the system may adjust the weighting in favor of the  1201  cornerstone design and display a lens optical design with a 1.2:1 ratio, for example. 
         [0098]    It will be understood that the progressive lens optical design determining system is capable of mixing any number of these cornerstone designs in any ratio. 
         [0099]    Each progressive lens optical design that is included in the final blended lens optical design is described by a Cartesian x,y,z point cloud (surface). Each surface must meet the following conditions: 
         [0100]    1. The x,y point set must be identical to that of the other surfaces. 
         [0101]    2. The surface normal at the origin must be parallel to the z axis. 
         [0102]    It is preferable that each surface also meet the following conditions: 
         [0103]    1. The surface power at the distance reference point should be zero. 
         [0104]    2. The x,y distance reference point should be identical to that of the other surfaces. 
         [0105]    3. The x,y reading reference point should be identical to that of the other surfaces. 
         [0106]    4. The addition power should be identical to that of the other surfaces. 
         [0107]    To blend the optical lens designs together, at each x,y point, the weighted average of the z axis coordinates is calculated according to the ratios (w) required: 
         [0000]        z   b =Σ i=1   n   z   i   w   i   (Eq. 1)
 
         [0000]    where:
       z i  is the z axis coordinate for the i th  cornerstone design,   w i  is a weight for the i th  cornerstone design,   n=number of designs, and       
 
         [0000]      Σ i=1   n   w   i =1  (Eq. 2)
 
         [0111]    A method for determining the required blending ratio (w) for each design will be described for an example embodiment. 
         [0112]    The output of zone tailoring and/or fine tuning will define the required horizontal distance between cylinder power contours of a certain level (e.g. 0.25D) at a distance reference point (α r ) and at a reading reference point (c r ). 
         [0113]    For each progressive lens optical design, from i=1 to i=n, at both distance and reading reference points, the horizontal width between contours is calculated, wherein: 
         [0114]    a i  is the distance reference point width for design i. 
         [0115]    c i  is the reading reference point width for design i. 
         [0116]    The predicted width between cylinder contours can then be calculated using starting values for the ratios (w). 
         [0117]    The predicted width between contours at the distance reference point is calculated using: 
         [0000]        a   p =Σ i=1   n   a   i   w   i   (Eq. 3)
 
         [0118]    The predicted width between contours at reading reference point is calculated using: 
         [0000]        c   p =Σ i=1   n   c   i   w   i   (Eq. 4)
 
         [0119]    An error value (e) can then be calculated as a measure of how far the predicted widths are from the target widths: 
         [0000]        e =( a   r   −a   p ) 2 +( c   r   −c   p ) 2   (Eq. 5)
 
         [0120]    The error (e) can then be minimised by changing the ratios w 1  to w n  using any suitable minimization method. 
         [0121]      FIG. 13  is a flowchart illustrating a process for operating a progressive lens optical design determining system according to one embodiment. In step  1301 , the user selects design attributes using zone tailoring. For example, the user may indicate whether they already use a progressive, bifocal, or single-vision lens and identify a relative importance of near, intermediate, and far areas of vision. In step  1302 , information output from the zone tailoring phase is used to produce targets for a progressive lens optical design that meets the user&#39;s inputs. 
         [0122]    In step  1303 , an optimization process begins to determine the proportions of a group of cornerstone designs to meet the desired progressive lens optical design. In step  1304 , the system evaluates whether optimization has converged. If the progressive lens optical design has not been optimized, then the process returns to step  1303  to continue the optimization process. 
         [0123]    When the progressive lens optical design has been optimized, the process moves to step  1305  where cornerstone designs are blended in the ratios determined by the optimization process. In step  1306 , a blurred image is generated from the blended cornerstone design. 
         [0124]    The blurred image is presented to the user, who indicates whether or not the progressive lens optical design is satisfactory in step  1307 . If the progressive lens optical design is acceptable, then the process is finished in step  1308  and the progressive lens optical design is used to manufacture lenses for the user. If the progressive lens optical design is not satisfactory, then the system determines if major alterations are needed in step  1309 . If major alterations are not needed, then the process accepts user alterations within predefined limits, such as modifications selected from two boundary progressive lens optical designs that meet the zone tailoring inputs. The process continues at step  1305  using the altered design. On the other hand, if major alternations are needed, then the process returns to step  1301  to allow the user to redefine the zone tailoring inputs. 
         [0125]    Many modifications and other embodiments of the invention will come to mind to one skilled in the art to which this invention pertains having the benefit of the teachings presented in the foregoing descriptions, and the associated drawings. Therefore, it is to be understood that the invention is not to be limited to the specific embodiments disclosed. Although specific terms are employed herein, they are used in a generic and descriptive sense only and not for purposes of limitation.