WO2003018253A1

WO2003018253A1 - Lens block and associated de-blocking apparatus and method

Info

Publication number: WO2003018253A1
Application number: PCT/CA2002/001313
Authority: WO
Inventors: Marc Savoie; Bernard Cormier; John Wilden
Original assignee: Micro Optics Design Corporation
Priority date: 2001-08-31
Filing date: 2002-08-27
Publication date: 2003-03-06
Also published as: EP1425134A1; CA2372766A1; JP2004538169A

Abstract

A method and apparatus are provided for deblocking a lens from a lens block in wich a fluid passage is provided through the lens block to a lens mounting surface adjacent which the lens is mounted. A pressurized fluid is introduced to the fluid passage and transmitted thereby to an interface between a lens mounting adhesive and a lens mounting surface. The apparatus includes a lens block and a receptacle for receiving the lens block, a clamp for securing the lens block to the apparatus and a pump for supplying pressurized fluid from a fluid source to the passage in the block. The lens block may also include an embedded RFID tag embedded in the lens block and a fluid pressure responsive piston mounted between a balance of said lens block and said lens.

Description

LENS BLOCK AND ASSOCIATED DE-BLOCKING APPARATUS AND METHOD

FIELD OF THE INVENTION This invention relates generally to the mounting of ophthalmic lens blanks and ophthalmic lenses to a lens block for support during a lens surfacing operation, and . the removal of a lens from a lens block after lens surfacing. -

BACKGROUND OF THE INVENTION

A traditional way to bond a lens blank to a lens block is through the use of a meltable adhesive substance such as wax. While waxes are a reasonably workable bonding agent, there are detriments to their use. Wax tends to be messy both in its injection and its removal. Wax tends to leave residue on the lens blank, requires considerable time to cool sufficiently to set (on the order of 15 minutes) and the heat imparted to the lens and stresses associated with setting may cause optical defects in the finished lens through associated warpage.

More recently adhesive compounds for lens blocking have been developed which are curable by exposure to ultra violet ("UN") and visible radiation rather than thermosetting. While such UN curable compounds have beneficial properties as compared to wax, they however present their own challenge with respect to stripping. Many of these compounds incorporate an agent that responds to a solvent to assist in softening the adhesive for deblocking. Such agents are however undesirable as typically they require considerable time to effect deblocking. Also, such agents may be susceptible to liquid lubricants used in the lens surfacing operation(s).

A common method for deblocking a lens mounted with a wax is to place the lens in a cylindrical tube which receives the lens block and engages a perimeter ofthe lens. The tube is then struck against a hard surface with the lens block facing the surface. The tube prevents the movement of the lens toward the surface while allowing the momentum ofthe lens block to separate it from the lens.

While using a tube in the traditional deblocking method to deblock a UN compound mounted lens may work as long as the adhesion isn't overly great, a ^' problem arises when there is insufficient mass in the block to provide adequate momentum. Conventional blocks were typically of metal. In order to cure a UN curable compound, it is desirable to use a UN transmissive plastic lens block. Obviously a plastic lens block will have significantly less mass than a metal one of similar dimensions.

It is an object of the present invention to provide a deblocking apparatus ("deblocker") and method which enables rapid deblocking without reliance upon inertial forces ofthe lens support for providing the deblocking force.

It is a further object ofthe present invention to provide a lens block for use with UN curable lens mounting compounds that provides even curing of the UN curable compounds.

It is a further object of the present invention to provide a radio frequency transmissive lens block enabling the use of an embedded RFID tag in a lens block.

SUMMARY OF THE INVENTION

A lens block is provided for blocking an ophthalmic lens. The lens block has a body with a base, a lens support surface opposite the base and engagement means for engaging a clamping means for securing the block to a deblocking apparatus. At least one passage extends through the body and fiuidly communicates with the lens support surface. The block is of a material transmissive to radiation having a wavelength suitable for curing a radiation curable compound for use in lens blocking. The engagement means may be a groove at least partially encircling the body generally parallel to the base.

In one embodiment the passage extends between the base and the lens support surface.

A deblocking apparatus is provided which has a housing with a receptacle for receiving a lens block. Releasable clamping means are associated with the housing to engage the lens block to secure the lens block to the receptacle. The apparatus has a fluid outlet for registering with a fluid passage inlet in the lens block. The apparatus further has a pump with a pump inlet for receiving a deblocking fluid, the pump fiuidly communicates with the fluid outlet for supplying pressurized fluid to the outlet. A fluid controller is provided to control flow ofthe deblocking fluid to the fluid outlet and a fluid seal is provided to effect a seal between the fluid outlet and the fluid passage inlet.

Preferably the deblocking apparatus has a cover attached to the housing for covering a lens mounted to the block during deblocking, the cover being movable between an open position allowing placement and removal of the lens block and a closed position for shielding an operator from the lens and the deblocking fluid. A latch is provided for releasably securing the cover in the closed position.

The cover may operably engage the clamping means to move the clamping means from a released configuration to an engaged configuration as the cover is moved from the open position to the closed position. The cover preferably has a lens impact damper which registers with the lens in the closed configuration to limit displacement ofthe lens away from the lens block. The clamping means may include at least one latterly swingable j aw pivotably connected to one of a housing and the receptacle and having a inwardly extending ridge for registering with the groove in the lens block. Each jaw may have a cam surface for registering with a corresponding cam surface on the cover to cause the jaw to urge the ridge toward the groove in response to the cover being urged toward the closed position.

The ridge and the recess maybe provided with corresponding tapered surfaces which cause the lens block to be urged towards the receptacle as the ridge is urged into the recess.

The deblocking fluid may be water. The pump may be pneumatically operable and the pump may supply pulses of water to the fluid outlet. The fluid controller may be a valve which controls the flow of pressurized air to the pump.

The lens block may have a groove extending into the lens mounting surface and encircling the fluid outlet.

An identifying tag may be imbedded in the lens block for providing encoded data as to the lens mounted to the lens block, the data being transmitted through the lens block.

The identifying tag may be an RF ID ("Radio Frequency Identification Tag") tag.

The lens block may include orientation indices for alignment ofthe lens block with a chuck of a lens generating machine. . The passage may slidingly receive a piston immediately adjacent the lens support surface, the piston being axially displacable by fluid pressure within the passage to extend from the lens support surface.

The piston may have a lens mounting surface facing away from the lens block which, in a retracted position ofthe piston is substantially flush with the lens support surface.

The piston may include an alignment indicator for indicating lens orientation and the piston and the passage adjacent the piston may be configured to axially orient the piston within the lens block.

The configuration for axially orienting the piston within the lens block may be by way of having the piston and the passage respectively shaped to register with each other in a fixed axial orientation.

The lens block may also have optical features such as a Fresnel lens formed in a bottom surface thereof to improve uniformity of light intensity on the UN curable compound.

The lens block may be translucent rather than transparent to cause at least some diffusion of light passing therethrough during curing of a lens mounted thereto to reduce shadowing.

The translucence may be derived by a surface finish ofthe lens block.

A method is provided for deblocking a lens from a lens block comprising the step of: (i) applying pressurized fluid through a lens block to an interface between a lens mounting face on the lens block and an adhesive securing the lens to the lens mounting face.

A method of deblocking a lens from a lens block comprising the step of: (ii) applying pressurized fluid to a fluid pressure responsive piston mounted between the lens and the lens block to cause the piston to urge the lens away from the lens block

In either method the deblocking fluid may be water and the method may include the further steps of: (iii) mounting a damper adjacent to the lens to limit movement ofthe lens away from the lens block during deblocking; and, (iv) shielding the lens block and the lens during de- blocking.

DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the present invention are described below with reference to the accompanying illustrations in which:

Figure 1 is a perspective view of a deblocker according to the present invention;

Figure 2 is a plan view from above of the deblocker of Figure 1 i an open configuration;

Figure 3 is a section on line 3-3 of Figure 2;

Figure 4 is an enlargement of the encircled area identified by reference E in Figure 3;

Figure 5 is a plan view from above of the deblocker of Figure 1 in a closed configuration;

Figure 6 is a section on line 6-6 of Figure 5; Figure 7 is an enlargement of the encircled area F in Figure 6;

Figure 8 is a perspective view from below of an alternate embodiment of a lens block according to the present invention;

Figure 9 is a view corresponding to Figure 8 but indicating in dashed lines a fluid passage and a passage for receiving an RFID tag; Figure 10 is a bottom plan view of the lens block of Figure 8 ;

Figure 11 is a view corresponding to Figure 10 but showing in dashed outline internal features not visible in Figure 10;

Figure 12 is an elevation of a lens block according to the present invention; Figure 13 is a view corresponding to figure 12 but showing internal details in dashed outline;

Figure 14 is an exploded perspective view of a further alternate embodiment lens block according to the present invention;

Figure 15 is a view corresponding to Figure 14 but showing internal details in dashed outline; Figure 16 is a section on line 16-16 of Figure 15;

Figure 16A is a bottom plan view ofthe lens block of Figure 14; Figure 16B is a section on line 16B-16B of Figure 16 A; Figure 16C is a perspective view from below ofthe piston portion ofthe lens block of Figure 14; Figure 17 is an exploded perspective view of yet another embodiment of a lens block according to the present invention;

Figure 18 is a view corresponding to Figure 17 but showing internal details in dashed outline;

Figure 19 is a section on line 19-19 of Figure 18; Figure 20 is a bottom elevation ofthe lens block of Figure 17;

Figure 21 is a section on line 21-21 of Figure 20;

Figure 22 is a perspective view of the piston portion of the lens block of Figure 17; Figure 23 is a perspective view of the bottom of a lens block according to the present invention including a Fresnel lens as an optical feature for diffusing light being shone therethrough;

Figure 24 is a bottom elevation corresponding to Figure 23; Figure 25 is a section on line 25-25 of Figure 24; Figure 26 is a bottom perspective of an embodiment of a lens block according to the present invention incorporating a curved bottom face as a feature for diffusing light during lens curing;

Figure 27 is a bottom elevation corresponding to Figure 26; Figure 28 is a section on line 28-28 of Figure 27; Figure 29 is a. bottom view of a lens block configuration similar to that of

Figure 23 but showing a more extensive Fresnel surface;

Figure 30 is a bottom elevation ofthe lens block of Figure 29; Figure 31 is a section on line 31-31 of Figure 30; and, Figure 32 is a schematic sectional view illustrating diffusion of light through a lens block having a planar base.

DESCRIPTION OF PREFERRED EMBODIMENTS

A deblocker according to the present invention is generally identified by reference 10 in the accompanying illustrations. A lens block for use in association with the deblocker 10 is generally identified by reference 100.

• The lens block 100 has a body 102 with a base 104, a lens support surface 106 opposite the base 104 and engagement means in the form of a groove 108 extending around the body 102. The groove 108 engages clamping means on the deblocker 10 in a manner which is described in more detail below.

A fluid passage 110 extends through the body 102 of the block 100 to provide a fluid conduit through the block 100 to the lens support surface 106. In the illustrated configuration the fluid passage 110 extends between the base 104 and the lens support surface 106. It will however be appreciated that this is not essential other than to provide a fluid inlet into the passage 110 which registers with a fluid outlet in the deblocker 10. Accordingly it may be possible to reconfigure the block 100 and the deblocker 10 to provide for a fluid inlet into the passage 110 other than through the base 104.

The lens block 100 may additionally have orientation indices such as holes 120 or a flattened portion about the base 122 to rotationally orient the block with a chuck of a lens surfacing machine.

The body 102 is preferably of a material such as a plastics material which is transmissive of light energy in the UN and visible wavelengths, assuming of course that it is desired to cure a UN curable lens mounting adhesive through the block 100.

Other materials maybe considered for radiation curable compounds which cure with radiation out of the UN and visible wavelengths.

• In practice it has been found that a lens block 100 is preferably translucent rather than entirely transparent. This is because the rate and degree of curing of UN curable lens blocking adhesives is effected significantly by the intensity of light in any given region ofthe adhesive. Accordingly any shadowing effect tends to cause anomalies which will eventually affect lens surface quality in subsequent lens surface generation.

A translucent rather than a transparent lens block causes diffusion ofthe light thereby more evenly distributing the light throughout the lens block and rniniπiizing any shadowing effect and thereby effecting a more even cure. Translucence may be achieved through any ofthe various known processes such as applying a translucent finish, molding the lens block with a textured surface, sandblasting to "roughen up" the surface or the addition of suitable light dispersing media in the raw materials from which the lens block is formed.

It is possible also to improve the uniformity of light intensity on the UN compound by incorporating suitable optical features in the lens block. For example, as illustrated in Figures 23 through 25 the lens block 100 may incorporate a Fresnel lens shown at reference 150 in its base 104. A further Fresnel lens may be incorporated higher up on the base as shown as reference 152 in Figures 29 through 31. Other configurations may also be possible however a Fresnel lens is advantageous in that it does not substantially effect the depth ofthe lens block 100 or its ability to rest on a flat surface.

Other optical features are possible. One such feature is illustrated in Figures

26 through 28. Instead of a Fresnel lens, a simple lens 160 is formed into the base 104. The fusion of light by the simple lens 160 is illustrated in Figure 28.

The optics ofthe block 100 should preferably be optimized based on the lens curvature is covered by a particular block. The base curve of the lens mounting surface 106 may be varied depending on the range of lenses to be supported thereby.

The improvement of incorporating a Fresnel lens 150 or other features to improve uniformity of light intensity on the UN compound may be adapted to transparent lens blocks 100 which lack the present deblocking arrangement. For example, it is expected that improved results would be obtained also with UN curable compounds of the solvent strippable kind.

A lens 200 is illustrated as being mounted to the lens mounting face 106 by an adhesive which is not shown but which would occupy a space 202 between the lens 200 and the mounting face 106. The deblocker 10 has a housing 12 to which is mounted a receptacle 14 for receiving the lens block 100. Clamping means in the form of a block clamp 16 are provided adj acent the receptacle 14 and may, as illustrated include a fixed part 18 and a laterally swingable jaw 20 pivotally connected thereto at a pivot 22 for movement about the pivot 22 is a direction illustrated by arrows 24. The jaw 20 is movable between a released configuration shown in Figures 1 through 4 and an engaged configuration shown in Figures 5 through 7.

The fixed part 18 and the j aw 20 have respective inwardly extending ridges 30 and 32 for registering with the groove 108 of the block 100. Preferably the ridges

30 and 32 have respective cam surfaces 34 and 36 which register with a corresponding cam surface 112 of the groove 108 to urge the block toward the receptacle 14 in response to the jaw 20 being urged toward the fixed part 18.

It will be appreciated that it is not necessary for the groove 108 to completely encircle the block 100. For example a pair of shorter grooves maybe provided and the ridges 30 and 32 maybe comparatively shorter. Other clamping means may also be utilized which have the desired effect of securing the block 100 to the receptacle 14, for example the block 100 could threadedly engage the receptacle 14 or be provided with downwardly extending prongs which are grasped by suitably configured pincers associated with the receptacle 14.

It will further be appreciated that the clamping means may include more than one jaw 20 and that each jaw 20 may be operably connected to the cover 80 in such a manner as to release and engage in response to movement ofthe cover 80 so as to avoid having to swing the jaw 20 as a separate step before closing the cover 80. 5 The deblocker 10 further has a fluid delivery port 40 with a fluid outlet 42 which registers with a fluid inlet 114 into the fluid passage 110. A seal in the form of an O' ring 44 may be provided about the outlet 42.

A pump 50 which may, as illustrated in Figure 1 be mounted within the housing 12 fiuidly communicates with the fluid outlet 42 through the fluid delivery port 40. 10 The pump 50 has an inlet 52 which receives a deblocking fluid.

The deblocking fluid may be water or another suitable incompressible fluid.

Compressible fluids such as air might also be utilized however they tend to impart an undesirable projectile force on the lens 200 upon deblocking. Incompressible fluids seem to yield more easily controllable results. The fluid may be stored in a reservoir

15 70 having an outlet 72, and an inlet 74.

Although the pump 50 may be manually or electrically operable, in the illustrated embodiment, an air operated pump 50 is utilized and receives compressed air from an air inlet 56 connected to a valve block 58 and controlled by a push button

60. The valve block 58 acts as a controller for controlling actuation ofthe pump 50

20 and therefore also acts to control flow of deblocking fluid to the fluid outlet 42.

In use, a lens block 100 with a lens 200 affixed thereto is secured to the receptacle 14 by the clamping means 16 with the fluid inlet 114 registering with the fluid outlet 42 and the base 104 sealingly engaging the receptacle 14 by virtue ofthe O ring 44. The pump 50 is energized and draws fluid into the pump inlet 52 25 pressurizes and discharges it through the fluid port 40 and through the fluid outlet 42. The pressurized fluid enters the fluid passage 110 in the block 100 and passes it to the lens support surface. The pressurized fluid then causes separation between the lens support surface 106 and the adhesive to deblock the lens 200. In practise it has been found beneficial to supply the fluid from the pump 50 in short "bursts" or "pulses" rather than under a continuous pressure. It has also been found beneficial to provided a shallow groove 116 extending into the lens support surface 106 and encircling the fluid passage 110 to avoid fluid escaping to one side rather than effecting total deblocking. It has also been found that a plurality of non- centralized fluid passages 110 provide consistent deblocking without having a groove 116. Presumably the combination of a plurality of fluid passages 110 and a groove 116 would also work however this may be somewhat redundant.

In order to capture the lens 200 when it deblocks and also to avoid deblocking fluid from spraying out from around the receptacle, 14, a cover 80 is provided which may be hingedly attached to the housing 12. The cover 80 is movable between an open position as shown in Figures 1 through 4 and a closed position shown in Figures 5 through 7. In the open position, the cover 80 allows placement ofthe lens block 100 and lens 200 on the receptacle 14. In the closed position, the cover , the lens 200 and lens block 100 to shield an operator from the lens 200 and the deblocking fluid.

The cover 80 may include a frusto-conical cam surface 82 which acts against a corresponding cam surface 26 on the jaw 20 to urge the jaw 20 toward its engaged position in response to a closing force being applied to the cover 80.

The cover 80 may have a latch 82 operated by a handle 84 for engaging the housing 12 to maintain the cover 80 in its closed position.

To avoid damage to the lens 200 which might otherwise occur by the lens 200 being hurled against the cover 80 upon deblocking a lens impact damper 86 is provided within the cover 80 in a location which registers with the lens 200 when the cover 80 is closed. The lens impact damper may be a resilient member extending between the cover 80 and the lens 200.

Although the deblocker 10 may be operated as a total loss system with respect to fluid usage, preferably the deblocking fluid will be captured and returned to the reservoir 54. This may be accomplished by providing a drain 56 in the top of the housing 12 and a drain outlet 60 from the housing 12 which fiuidly communicates with the inlet 74 into the reservoir 704. Recirculation may be gravity or pump assisted as required. Alternatively, the housing 12 itself can be configured to act as a sump.

In order to avoid passage of lens mounting adhesive into the passage 110 in the lens block 100 during blocking, a removable blanking pin (not shown) may be used to fill the passage 110 during blocking.

An advantage to using a plastic lens block 100 is in lens identification. As plastics are transmissible to radio frequency signals, an RF marker (or "RFID tag") 300 containing encoded information including an identification code and possibly other information on such things as lens orientation, type and shape may be embedded in the lens block 100. Conventional metal blocks will not transmit radio frequency signals. A receptacle 302 is illustrated extending into the lens block 100 for receiving the RFID tag 300.

Figures 14 through 16 illustrate an alternate embodiment of a lens block according to the present invention. Figures 17 through 22 illustrate yet another alternate embodiment of a lens block according to the present invention. As most of the features of the two alternate embodiment lens blocks are common to the lens block 100 described above, like components are numbered with like reference numerals and the above description applies. The principal difference between the two alternate embodiment lens blocks

100 and the lens block described above is in the mounting of a fluid responsive piston 140 in the fluid passage 110 adjacent the lens mounting surface 106.

As illustrated in Figures 14 through 19, the passage 110 has a bore 130 at an end opposite the inlet 114 which slidingly receives the piston 140 immediately adjacent the lens support surface 106. The piston 140 is axially displaced along the bore 130 by fluid pressure along the passage 110 to cause it to extend above the lens support surface 106.

The piston 140 has a lens mounting surface 146 which, in a retracted position illustrated in Figures 16 and 19 substantially flush with the lens support surface 106 adjacent thereto.

In use, the piston portion 140 ofthe lens mounting block 100 is inserted ή to the bore 130 of the body 102. A lens 200 (not illustrated in Figures 9 through 19) is mounted to the lens mounting block 100 as described above in the previous embodiment using suitable lens mounting adhesives.

In order to deblock the lens 200, a similar method to that described above is employed namely, pressurized fluid is introduced into the fluid passage 110. Unlike the above description, deblocking is not merely a function of pressurized fluid acting directly against the lens 200 but instead, the fluid acts to a large extent against the piston 140 causing it to move axially along the bore 130 toward the lens 200 to press the lens off of the lens support surface 106. Some fluid will likely escape between the piston 140 and the bore 140 and act as a secondary deblocking mechanism much as described above. It has been found in practice that the use of a piston 140 provides more consistent deblocking than merely applying fluid pressure. If only fluid pressure is utilized, occasionally the fluid will escape before full deblocking is realized. Once the fluid finds an escape path, it becomes difficult (if at all possible) to achieve enough pressure to complete deblocking. The use of apiston 140 ensures a minimum displacement of the lens 200 away from the balance of the lens block 100 before fluid escape becomes significant.

In practice it has been found that in most cases the piston 140 remains adhered to the lens 200 after deblocking from the remainder ofthe block 100. This can be advantageous as the piston provides a gripping surface smaller in diameter than the lens 200 which may be used to manoeuver the lens in a subsequent edging operation. In the case of asymmetrical lenses, lens orientation must be maintained during edging for the lens to be properly oriented once mounted into frames. Accordingly some provision should be made in the piston 140 to provide lens orientation information.

As illustrated in Figures 14 through 16 embodiment, one or more grooves 142 and 144 may be provided in piston 140 which would interact with a suitable key (not illustrated) in the bore 130 to maintain orientation between the piston 140 and the body ofthe lens block 102 when the piston 140 is in its retracted position. The same grooves 142 and 144 may then register with whatever chuck or other holding means is used during the edging operation.

Other alignment indicators than grooves and keys may be utilized. For example the bore 130 and the piston 140 may be formed in an elliptical of other non- circular cross- section shape.

The above description is intended in an illustrative rather than a restrictive sense. Variations to the exact apparatus and methods described may be apparent to those skilled in the relevant art without departing from the spirit and scope of the invention as defined by the claims set out below.

Claims

1. A lens block for blocking an ophthalmic lens, said lens block comprising: a body having a base, a lens support surface opposite said base; and, at least one passage extending through said body and fluidly communicating with said lens support surface.

2. The lens block of claim 1 wherein said block further comprises: engagement means for engaging a clamping means for securing said block to a deblocking apparatus; and, said engagement means is a groove at least partially encircling said body generally parallel to said base.

3. The lens block of claim 1 wherein: said passage extends between said base and said lens support surface; and, said block is of a material transmissive to light having a wavelength at least in the ultra violet spectrum.

4. The lens block of claim 2 wherein: said passage extends between said base and said lens support surface.

5. A deblocking apparatus comprising: a receptacle for receiving a lens block; releasable clamping means for engaging said lens block to secure said lens block to said receptacle; a fluid outlet for registering with a fluid passage in said lens block; a pump having a pump inlet for receiving a deblocking fluid, said pump fluidly cornmunicating with said fluid outlet for supplying pressurized fluid to said fluid outlet; and, a fluid controller for controlling flow of said deblocking fluid to said fluid outlet.

6. The deblocking apparatus of claim 5 further having: a cover attached for covering a lens mounted to said block during deblocking, said shield being movable between an open position allowing placement and removal of said lens block and a closed position for shielding an operator from said lens and said deblocking fluid; a latch for releasably securing said cover in said closed position; and, a fluid seal for effecting a seal between said fluid outlet and said fluid passage inlet.

7. The deblocking apparatus of claim 6 wherein: said shield operably engages said clamping means to move said clamping means between a released configuration and an engaged configuration as said shield is moved from said open position to said closed position; and said shield has a lens impact damper which registers with said lens in said closed configuration to limit displacement of said lens away form said lens block.

8. The deblocking apparatus of claini 7 wherein: said clamping means includes at least one moveable jaw connected to one of said housing and said receptacle and having an inwardly extending ridge for registering with, a groove in said lens block; and, each said at least one jaw has a cam surface for engaging a corresponding cam surface on said cover to cause said jaw to urge said ridge toward said groove in response to said cover being urged toward said closed position.

9. The deblocking apparatus of claim 8 wherein: said ridge and said recess are provided with corresponding tapered surfaces which cause said lens block to be urged toward said receptacle as said ridge is urged into said recess.

10. The deblocking apparatus of claim 9 wherein: said deblocking fluid is water; said pump is pneumatically operable; said pump supplies pulses of water to said fluid outlet; and, said fluid controller is a valve which controls the flow of pressurized air to said pump.

11. . A lens block as claimed in claim 4 wherein: said lens block has a groove extending into said lens mounting surface and encircling said fluid outlet.

12. A lens block as claimed in claim 11 further having: an identifying tag embedded therein for providing encoded data as to the lens mounted to said lens block.

13. A lens block as claimed in claim 12 wherein: said tag is a RFID ("radio frequency identification") tag.

14. A lens mounting block as claimed in claim 13 further having: orientation indices for alignment of said lens block with a chuck of a lens surfacing machine.

15. The apparatus of claim 5 further having: a shield for shielding an operator from said lens and said deblocking fluid during deblocking.

16. A method of deblocking a lens from a lens block comprising the step of:

(i) applying pressurized fluid through said lens block to and adhesive interface between a lens mounting face on said lens block and said lens to said lens.

17. The method of claim 16 wherein said deblocking fluid is water, and including the further step of:

(ii) mounting a damper adjacent said lens to limit movement of said lens away from said lens block during deblocking; and,

(iii) shielding said lens block and said lens during deblocking.

18. A method of deblocking a lens from a lens block comprising the step of:

(i) applying pressurized fluid to a fluid pressure responsive piston mounted between said lens and said lens block to cause the piston to urge said lens away from said lens block.

19. The method of claim 18 wherein said deblocking fluid is water and including the further steps of:

(iii) shielding said lens block and said lens during deblocking.

20. The lens block of claim 1, 2, 3 or 4 wherein: said passage slidingly receives a piston immediately adjacent said lens support surface, said piston being axially displacable by fluid pressure within said passage to extend from said lens support surface.

21. The lens block of claim 20 wherein: said piston has a lens mounting surface facing away from said lens block; and, said piston has a retracted position wherein said lens mounting surface is substantially flush with said lens support surface.

22. The lens block of claim 21 wherein: said piston includes an alignment indicator for indicating lens orientation for lens edging or other subsequent alignment tasks; and, said piston and said passage adjacent said piston are configured to axially , orient said piston within said lens block.

23. The lens block of claim 22 wherein: said configuring is by way of said piston and said passage being respectively shaped to register with each other in a fixed axial orientation.

24. The lens block of claim 3, 4, 11, 12, 13, 14, 20, 21, 22 or 23 wherein: said lens block is translucent rather than transparent to cause at least some diffusion of light passing therethrough during curing of a lens mounted thereto to reduce shadowing.

25. The lens block of claim 24 wherein: said translucence is derived by a surface finish of said lens block.

26. The lens block of claims 3, 4, 11, 12, 13, 14, 20, 21, 22 or 23 wherein: said lens block includes an optical feature in at least said base for evening the uniformity of intensity of light passing therethrough during curing of a lens mounte thereto.

27. The lens block of claim 26 wherein: said optical f ature is a member selected from the group consisting of a Fresnel lens atod a simple lens which is formed into said base.

28. A lens block for blocking an ophthalmic lens, said lens block comprising: a body having a base and a lens support surface opposite said base; said block being of a material which is transmissive to light having a wavelength^ within at least in the ultra violet spectrum; said lens block including an optical feature in at least said base for evening the uniformity of intensity of light passing therethrough during curing of a lens mounted thereto.

29. The lens block of claim 28 wherein: said optical feature includes at least one member selected from the group consisting of a Fresnel lens profile, a simple lens profile and translucence.

30. The lens block of claim 29 wherein: said translucence is achieved by a surface finish of said lens block.

31. A lens block for blocking an ophthalmic lens wherein: said lens block is RF transmissive; and said lens block includes an imbedded RFID tag.