WO1997043672A1

WO1997043672A1 - Holographic coaching

Info

Publication number: WO1997043672A1
Application number: PCT/GB1997/001294
Authority: WO
Inventors: John Scott Strachan; Derek Scott Peterson
Original assignee: John Scott Strachan; Derek Scott Peterson
Priority date: 1996-05-10
Filing date: 1997-05-12
Publication date: 1997-11-20
Also published as: GB9609841D0; AU2782897A

Abstract

A coaching aid uses a replay unit in which a hologram (6) is illuminated by a light source (1) via a lens (2) and a holographic mirror (4) acting as a spectral filter. An image of, for example, a circle is produced at an apparent distance of some feet. The replay unit may be mounted on an item of headwear and used in training golfers by making them aware of head alignment with respect to the ball.

Description

Holographic Coaching

This invention relates to a holographic device for use in coaching or training in sporting activities.

Many sporting activities depend on the co-ordination of parts of the body in unusual and awkward ways. Mastery of these sporting activities is often made more difficult by the absence of any direct feedback as to whether or not that co-ordination is working properly or not, since as a beginner, or often even after considerable experience, a player is naturally unsure of how the various parts of the body should feel when the particular sporting activity is performed properly. A coach is usually required, preferably early in a career, to train the player in the best way and to try to instil a body memory of the right feel.

The present invention relates to the use of a hologram to provide visual feedback, in one example, of head movement and, in a second example, of hand movement. Such holograms may be used as self coaching aids or, in cases where the sporting rules allow or do not apply, in the pursuit of the sporting activity. Golf is a classic example of a sport which can benefit from this type of coaching aid.

This sport requires the co-ordination of the whole body in a smooth total rhythm for any degree of success to be achieved. When the whole body is involved in any activity it tends to follow the head to an extraordinary degree. Unfortunately, the instinct tends to want to move the head not to follow the direction of the eyes but to precede the direction of the eyes. In golf this invariably leads to a tendency to lift or turn the head to follow the ball before the ball has been hit. This motion disturbs the body's equilibrium and the result is a miss-hit. Once this habit develops it is extremely difficult to cure because there is no direct feedback to show the brain the position of the head.

Over the years various gadgets have been developed to try to solve this problem. Devices to physically restrain the head, electronic devices to provide beeps in response to motion, and systems to provide a tactile feel, but because of the body's natural ability to co- ordinate to the eye this must surely be the best approach to the problem. One idea was a pair of spectacles with a slit to try to force the head to line up the slit with the ball. This would be unsatisfactory since apart from the annoying hindrance to vision, the close proximity of the slit to the eye would mean that too much freedom of movement would still be possible because of the nature of the eye's focus.

Another sporting field to which the present invention can be applied is that of pistol shooting. In pistol shooting the aim depends on the correct alignment of the front and rear sights of the pistol with the target. In practice the alignment of the fore sight with the rear sight is considerably more important than the apparent alignment of the sights with the target. This is because of the perspective effect of the proximity of the pistol and the distance of the target. The natural tendency is to be distracted by the alignment of the sight with the target and to snatch at the trigger pulling the gun out of any alignment it may have had. One solution to the problem is the laser gun sight which projects a spot on the target but this is unsatisfactory because of the expense and the poor laser reflectivity of most targets.

The present invention provides a holographic replay unit mounted on a structure attachable to the head or body of a person, or to an article held by a person, to present an apparent image sufficiently distant from the replay unit to give a clear indication of small angular motions of the replay unit.

A pair of such replay units may be used and be adjusted to present a stereoscopic cue to the viewer at a chosen depth when mounted in front of both eyes.

The replay unit may have a self contained illumination source directly illuminating the hologram, which may be either of the transmission or reflection mode; the illumination source position may be independently adjustable to adjust the apparent position of the replayed image.

Alternatively, the replay unit may have a self contained illumination source illuminating the hologram by means of an intermediate holographic mirror of narrow bandwidth or an intermediate narrow bandwidth filter; where a holographic mirror is used, its position may be adjustable to adjust the apparent position of the replayed image.

The invention also provides a coaching aid comprising a replay unit as defined above mounted on an item of headgear, such as a cap or a spectacle frame.

Further, the invention provides a coaching unit comprising a replay unit as defined above mounted on a target weapon, the weapon suitably being selected from pistol, rifle, smoothbore weapon, crossbow, and longbow.

The illumination source may be the output of a fibre optic.

Embodiments of the present invention will now be described, by way of example only, with reference to the drawings, in which: Fig. 1 is a perspective view showing one form of holographic replay unit forming one embodiment of the invention; Fig. 2 is a plan view corresponding to Fig. 1; Fig. 3 is a schematic perspective view illustrating the replay unit of Figs. 1 and 2 in use; Fig. 4 is a schematic perspective view of a modified embodiment.

The first example of this invention is a head coaching aid which consists of a holographic image of, for example, a circle placed at an apparent distance of approximately five feet behind the plane of the hologram. The hologram is then mounted on a novel replay device which can be mounted comfortably on a hat or spectacle frame. The replay device allows adjustment of the apparent position of the image of the circle so that it can be brought to a comfortable position for viewing in the normal stance. Since the image is approximately the same apparent distance to the eye as the golf ball in a putting or driving stance it is in the same focal plane for the eye and so the brain can comfortably accommodate the ball and the circle at the same time. Since the apparent position of the circle depends on the position of the head, a player will be constantly aware of any head movement and will be able to see whether it is side to side forward or back or up and down. This will quickly train the player to keep the head still during the stroke and a consequent rapid increase in the consistency of the stroke.

The apparent position of the image away from the viewer may be adjusted by adjusting the angular relationship between the light source and the hologram.

A second example is a pistol sight.

As in the golf coaching aid a hologram is made which projects a suitable image such as a circle or a cross to a point well in front of the pistol. Once again adjustments in the angle of the illumination source and the angle of the hologram can be made to line the image up with the projectile's impact point at a chosen range. While in theory the hologram could be made to produce an apparent image at many metres distance, in practice an image of only two to three metres is nearly indistinguishable from a longer range image. The effect is of a fore sight which for all practical purposes behaves as if it was projected on the target itself. This means it has all the accuracy possible with a laser sight but is totally unaffected by the reflectivity of the target or the ambient light. While such a sight would be of permanent use in hunting or military applications it is expected that its use would be quickly prohibited in target competitions. Even so the muscular habits developed during its use are useful in self coaching and a rapid improvement in score can be expected with its use which will carry over as better muscular control when the shooter returns to conventional sights for competition.

The basic holographic image replay unit consists of the following components as shown in Figs 1 and 2.

A high brightness light emitting diode or laser diode 1 suitably powered sends a beam of light through lens 2; the rays 3 reflect from a holographic mirror 4 as the rays 5. The holographic mirror 4 serves the two purposes of collimating the light from the diode 1 and of narrowing the spectral line of the light; this serves to improve the definition of the holographic image. This is important for a sharp image at a long apparent distance but in some applications where a perfect image is unimportant it may be dispensed with.

A holographic image of a target circle is formed on a light transmissive plate 6. The rays 5 replay the holographic image on the plate 6. The lens 2 may in some devices be supplemented with a narrow band filter, particularly when the hologram is of the transmission mode and the light source is a LED.

The holographic 6 may be manufactured by conventional methods well known in the art. For convenience and low cost, one suitable form of manufacture is by exposing a photopolymer material to an image of the desired target circle and to a reference beam.

The holographic mirror 4 is of a type standard in the literature, consisting essentially of a reflection hologram formed by exposure to main and reference beams with no image. The use of a holographic mirror is preferred, since this allows the light source used in the replay unit to be relatively broad-band, for example a conventional LED. With narrower bandwidth sources such as narrow bandwidth LEDs or laser diodes, it would be possible to replace the holographic mirror with a bandpass filter, or to dispense entirely with such components.

The assembly shown in Figs 1 and 2 can be mounted under a sun visor or on a spectacle frame for sports such as golf or snooker. For shooting it would be mounted on a pistol frame as an addition to or a replacement of the normal sight. Fig. 3 illustrates a replay unit 10 mounted under the brim of a cap 11 to produce an image 12 at an apparent distance of some metres.

When not illuminated the hologram is invisible and the assembly provides an unobstructed view of the real world beyond. When illuminated the image appears as a solid in space. The image will move as if it was solidly mounted by an invisible structure to the holographic assembly, and thus any motion of the hologram can be seen as a motion of the image against the background of the real world. The hologram may be either transmission or reflection mode and the replay unit may be viewed from either side depending on which type of hologram is used.

The apparent distance of the image can be adjusted by altering the angular relationship between the illumination source and the hologram. In a given product, a fixed apparent distance may be selected as an average suitable for most users. Alternatively, user adjustment may be provided for example by making the light source movable with respect to the replay device, or by providing means for adjustably tilting the holographic mirror with respect to the hologram; in either case a simple adjusting screw would be sufficient.

In a refinement of the device for applications where distance measurement is important, two such replay units can be arranged in front of the eyes and adjusted to fuse the replayed images as a stereoscopic pair. The focus of the eyes and stereoscopic perception combine to give the brain information relating to depth perception. In this configuration the stereoscopic image can be made to fuse at the distance desired. In the case of a golfing coaching aid the image would be made to fuse at the plane of the golf ball as shown in Fig. 4.

In Fig. 4 the replay units A are adjusted to the angle represented by the lines D and D to fuse the images at B at the depth of the golf ball C. Such an arrangement would mean that as the golfer's head moved up and down while the ball was held in focus the holographic images would fuse and unfuse. This would give a more pronounced depth cue than a single hologram. Such a refinement would not normally be advantageous but would be useful in, for example, the diagnosis of loss of form in an expert golfer where more precise information is required than the less dramatic cues provided by a single replay unit.

Modifications may be made to the foregoing embodiments within the scope of the claims. For example, instead of a LED or other light source illuminating the hologram directly or via a mirror, a fibre optic system may be used to transmit into the replay unit from a relatively remote source. This could be of utility in making the physical layout more flexible.

Claims

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1 A holographic replay unit mounted on a structure attachable to the head or body of a person, or to an article held by a person, to present an apparent image sufficiently distant from the replay unit to give a clear indication of small angular motions of the replay unit.

2 A pair of replay units each according to Claim 1, adjustable to present a stereoscopic cue to the viewer at a chosen depth when mounted in front of both eyes.

3 A replay unit as in Claim 1 with a self contained illumination source directly illuminating the hologram which may be either of the transmission or reflection mode.

4 A replay unit as in Claim 3 where the illumination source position is independently adjustable to adjust the apparent position of the replayed image.

5 A replay unit as in Claim 1 with a self contained illumination source illuminating the hologram by means of an intermediate holographic mirror of narrow bandwidth or an intermediate narrow bandwidth filter.

6 A replay unit as in Claim 5 where a holographic mirror is used and its position is adjustable to adjust the apparent position of the replayed image. 7 A replay unit as in Claim 3 to 6 where the illumination source is the output of a fibre optic.

8 A coaching aid comprising a replay unit in accordance with any of claims 1 to 7 mounted on an item of headgear.

9 A coaching unit comprising a replay unit in accordance with any of claims 1 to 7 mounted on a target weapon.

10 A coaching aid in accordance with claim 9, in which the target weapon is selected from pistol, rifle, smoothbore weapon, crossbow, and longbow.