The present invention relates to a device for helping to prevent the unauthorised reading of personal identification numbers known as PIN numbers used for example in order tQ gain cash or bank account information from automatic teller machines (ATM's) or when paying for goods or services by credit or debit cards using "chip and pin".

ATM's are often fitted in the outer wall of a bank or building society and are increasingly common in shops and pubs so they are readily accessible by the general public. Also chip and pin apparatus are to found in almost all retail outlets.

A problem with this is that when someone uses an ATM or chip and pin apparatus it is relatively easy for another member of the public to see the number tappόd into the ATM or chip and pin keypad by the user, for example by simply looking over his or her shoulder. Also it is known for those who are intent on committing fraud to be able to locate a camera or mirrors in the ATM hole to enable illegal reading of the pin number being tapped in. In the vast majority of cases people can access their money with confidence but this type of fraud is on the increase and there is a particular vulnerability for those using ATM's or chip and pin apparatus in busy affluent areas and crowded venues.

It is an aim of the present invention to reduce this risk and to this end there is provided a device for helping to prevent the unauthorised reading of

personal identification numbers, comprising a plurality of light transmitting means adapted to be located over a numeric or alpha/numeric display, the light transmitting means being such that in use the display can only be seen when viewed from a specific range of angles and/or distances.

The light transmitting means may comprise a plurality of apertures.

The apertures may be covered with, or filled with, a transparent plastics material.

The light transmitting means may be defined by a plurality of tubular apertures.

The tubular apertures may be arranged in cells.

The light transmitting means may be defined by an array of interleaved slotted strips.

The array may comprise a first row of strips extending parallel with each other and a second row of strips also extending parallel with each other and perpendicular to the first row so as to form apertures of substantially rectangular cross-section.

Each strip of the first row may comprise a plurality of slots extending obliquely to the longitudinal axis of the strip and each strip of the second row may comprise a plurality of slots extending perpendicularly to the longitudinal axis of the strip.

The light transmitting means may be defined by a plurality of parallel tubes united together and set in a sheet of, for example, plastics material.

The tubes or interleaved strips may be made from a variety of materials such as aluminium or a similar material.

The tubes may have a circular or elliptical cross-section.

The present invention also extends to apparatus comprising a numerical or alpha/numerical display a plurality of light transmitting means located over the display at such a spacing as to permit a user of the apparatus to touch the display below the light transmitting means, the light transmitting means being so disposed as to permit only the user of the apparatus to see the display via the light transmitting means .

The width of each aperture is preferably approximately half its depth.

Embodiments of the present invention will now be described by way of example and with reference to the accompanying drawings in which:

Figure 1 shows a perspective view of part of the light transmitting means of the present invention,

Figure 2 shows a strip used in defining the light transmitting means,

Figure 3 shows another strip used in defining the light transmitting means, which strip is in use interleaved with the strip shown in figure 2,

Figure 4 shows a perspective view of part of a different light transmitting means from that illustrated in figure 1 ,

Figure 5 shows a known ATM incorporated in the wall of a building, and

Figure 6 shows an ATM comprising a device according to the present invention.

Referring to figure 1 there is shown light transmitting means 1 comprising an array of strips 2 and 3 as shown in figs 2 and 3. Each strip 2 comprises a series of slots 4 which extend obliquely to the longitudinal axis of the strip 2 and the strip 3 comprises a series of slots 5 which extend perpendicularly to the longitudinal axis of the strip 3. Preferably the depth of each slot in both strips 2 and 3 is twice the width of the slots 4, 5. A typical width of each slot is 2.5 mm

The number of slots in each strip depends on the dimensions of the display and is readily adaptable to the dimensions of the display. In use each strip 3 extends perpendicularly through each strip 2 so as to form a series of apertures having an approximately rectangular cross-section.

The array of strips 2 and 3 are held together by being set or embedded in a mass of transparent plastics material (not shown) which hold the array in a particular position.

Arrows 7, 8 and 9 in figure 1 show the paths of sight from an eye positioned at locations 10, 11 and 12 respectively. As can be seen, only arrow 7 reaches the display or keypad illustrated schematically by reference numeral 13. Arrows 8 and 9 hit the side of the light transmitting apertures 1 and, therefore, do not reach the keypad 13. This means that only a person positioned with his or her line of sight along arrow 7 will be able to see the keypad 13. The arrow 7 corresponds to the line of sight of a user standing in the normal position for using an ATM. Another person looking over the user's shoulder at position 11 or to the side at position 12 would not be able to see the keypad 13 and, therefore, could not see the number tapped in by the user.

The array is in use located above the keypad 13 at a distance sufficient to enable a user of an ATM to place his or her hand below the array and on the keypad but insufficient to permit the insertion of a camera.

In an analogous manner it would also not be possible for a camera situated in the ATM to read the "PIN" number of the user.

Referring to figure 4 there shown light transmitting means 14 which performs the same function as that illustrated in figure 1. However, in figure 4 the light transmitting means 14 comprises an array of cylindrical cells 15 which are set in a transparent plastics material (not shown). As in the

embodiment illustrated in figures 1-3, arrows 16, 17 and 18 show the paths of sight from an eye positioned at different locations. Only an eye looking along the direction of arrow 16 will be able to see the keypad below the light transmitting means 15.

A manufacturing and economic advantage of the embodiment shown in figure 4 is that it can be made by setting a bundle of tubes (of for example aluminium) in a transparent plastics material to form a block. The block can then be sliced into sheets and each sheet located above the keypad 15 at the appropriate angle.

Figure 5 shows a known ATM incorporated in the wall 19 of, for example, a bank or building society. The ATM comprises a conventional screen 20 and an alpha numeric display such as a touch pad 21.

Figure 6 shows an ATM which like the ATM illustrated in figure 5 has a screen 21 and a touch pad 22. However, this ATM comprises a device 23 according to the present invention as described above in relation to any of figures 1 to 4 and located above the touch pad a sufficient distance to enable the user of the ATM to place his or her hand between the touch pad 21 and the device 23.

Although the present invention can be incorporated in existing ATMs, this may be regarded by banks or ATM manufacturers as expensive. The next generation of ATMs, however, could easily incorporate the present invention during manufacture at a modest extra cost, which would soon be recouped by avoiding the need to compensate users who would otherwise be

defrauded. It is also important for retailers and financial institutions to be seen by the public as taking customer security seriously.

Although the embodiments described above with reference to the accompanying drawings comprise light transmitting means of rectangular or circular cross-section, the light transmitting means may have a variety of cross-sections such as triangular or hexagonal.