The present invention concerns a device for the screening in the fog, consisting in an optic-electronic complex with 100 to 7000 micron electromagnetic waves, with a microcell screen.

It is well known that the radars known until now are not suitable for the application on vehicles and similar, due to the considerable encumbrance and of the excessive elec¬ trical input and cost.

It is the aim of the present invention to realize a devi- ce mounted on vehicles and similar, with a minimum encum¬ brance, moderate costs and electrical input, for the de¬ tection and screening in the fog of any other vehicle or similar.

The aim set forth is reached by means of a device with e- lectromagnetic waves, with a wave length interval from 100 to 7000 micron, placed between the end of the infrared ra¬ diations and the beginning of the microwaves; said waves are picked up by a microcell screen consisting in very small sensitive elements placed like a chess-board, consisting in known material, suitable for the detecting of the radiations corresponding to the wave length to the extreme infrared, altered with elements suited for the detection of the ini¬ tial microwaves.

The advantage of the device is evident, s the waves corre¬ sponding to the interval chosen and with the provided pow¬ ers travel without a considerable input even in the most strong fog, up to distances of many hundred meters, allow- ing the detection of the presence of vehicles or means of any kind.

Furthermore, the device according to the present invention comprises means for the identification of the distance of said vehicles or similar.

The present invention will be described more in detail he- reinbelow relating to the attached drawings in which some preferred embodiments are shown.

Figure 1 shows a scheme of a device for the screening in the fog, according to the present invention.

Figure 2 shows a perspective view of-the functioning of the device of figure 1.

Figure 3 shows a detail of a monitor for the screening of the vehicles.

Figures 4 and 5 show a scheme of a variant of the device ac¬ cording to the present invention.

Figure 6 shows a block scheme of the device according to the present invention.

The figures show a device for the screening in the fog, with electromagnetic waves from 100 to 7000 micron and microcell screen, mainly comprising lights 1, 2 and 3 provided in the back part of the vehicles and emitting radiations 4 which change the impact angle on the screen 6 according to the di¬ stance of the preceding vehicle from the following one. In the case of the light 3 corresponding to a more distant ve¬ hicle, said radiations fall on the objective (divergent lens) of hole 5 of the receiver, placed on a vehicle in arrival and strike the sensitive screen 6, shown with dotted lines, in area 7. In a similar way the beams of the lights 1 and 2 reach areas 8 and 9 of said screen 6.

For what concerns the functioning of the device, when the beams excite the area 7 of the screen 6, they cause the con¬ tact with the dotted circuit 10, battery fed and comprising an eventual signal amplification. The same happens for the lights 2 in area 8, with a contact to dotted circuit 11 and for lights 3 in area 9 with a contact to circuit.12, marked with a continuous line.

Therefore, circuit 10 lights alarm 14 with an eventual wery slow intermittence that lightens the immage of the vehicle printed thereon and signals the distance of about 100 meters of the beams.

Circuit 15 lignhtens alarm II with the image of a vehicle greater than the first one and signals 50 at quick intermit-

tence. Circuit 12 lightens alams 15 marked by the image of a vehicle at maximim width and marks 20 with continuous sound. Therefore, when the vehicle 17 receives by means of device 6 the beams of a vehicle of any kind preceding the same of 100 meters or more, i.e. vehicle 3, the fact is noticed to the driver by alarm 14.

When the preceding vehicle is at a distance of 50 meters, it is noticed by alarm 15, when it is at a distance of 25 meters by alarm 15. The alarms 14, 15 and 15 are placed in supporting frame 18, of very small dimensions which, e.g., may be 3 cm by 15 cm, placed on the board in front of the driver.

Said frame having a thickness of only 1 cm, may be turned o- ver by the movement of the indicator 19 and it may also be encased in the plane, when it is not used, i.e. in a day with¬ out fog. For what concerns the kind of electromagnetic radia¬ tions emitted by the lights being of dimensions not superior to the usual reflectors placed above the bumpers or below the indicator block it should be noted that obviously the optimal wave length must be defined during the realization and expe¬ rimentation of the prototype, but that however the area to be exploited is comprised between the last part of the infra¬ red radiation, i.e. a wave length of 100 micron and more, and the first part of the microwaves, i.e. a wave length from 100 to 7000 micron and more.

Furthermore, figure 3 shows the monitor 20 of small dimen¬ sions that may be extractable from the plane above the board or also be placed otherwhere and which, by means of a single push button, may be inserted to the television antenna on board and therefore used as a usual television.

In detail, it is to be noted that the whole complex may be mounted in various points of the whole front part of the ve¬ hicle.

For example: above or below the bumper, between the lights of the vehicle and the radiator, inside the roof, above or aside of the driving mirror, or also covered by the sun¬ shade, below or aside of the windscreen, etc. Said device may be easily electrically and thermically screened, so as not to be subject to various interferences.

For what concerns the functioning of the emitting device, and relating to the block scheme of figure 6, the three lights 1, 2 and 3, mounted on the back part of the vehicle through the stabilizer 21 battery-fed operate the modulator 22 that causes the diode 23, having a transmitting resound¬ ing cavity R, to emit said radiation from 100 to 7000 micron, which may be produced also by other known means.

For what concerns the reception of said electromagnetic wa¬ ves, by means of the device placed in the front part of the vehicle the wave emitted by the lights strikes the receiv¬ ing 24 cavity R provided with a diode with a low frequency

signal with an amplitude proportional to the emission di¬ stance, as a modulating waves is associated to the carry¬ ing one; from the diode the signal passes to the only am¬ plifyier 25 or to a plurality of a plifyiers, and from these to a band filter 26 for the elimination of the am¬ bient disturbances, from which only the modulating may get out which through the comparator 27 with modulation amplitude at three adjustable levels with variable resi¬ stances set for the three distances, reaches the three alarms 14, 15 and 16 that mark the 100, 50 and 20 meters, i.e. the interval existing between the preceding vehicle and the following one.

In the variant according to figures 4, 5 and 6 the diver- gent lens 5 is replaced by a hole of very few mm and ve¬ ry little specular blades 28 so as to obtain a greater selection, i.e.spreading of the beams coming from emit¬ ting lights T, 2 and 3 and that strike the five sensiti¬ ve areas 13, diode, insulating cavity R or other means. It shall be underlined that said baldes may be inserted also keeping lens 5 in such a way as to obtain a greater spreading of the beams.

In a possible variant, in case of damage of the device or according to the wish of the driver, should the emitting lights placed in the back part of the vehicle, it will be sufficient to light a light placed in the front part of

the vehicle, emitting electromagnetic waves with a wave length from 100 to 7000 micron, so that the beams thereof reflected on the preceding car may operate the receiving device, corresponding to block 24 of the scheme of figu¬ res 4, 5 and 6 and shown in the particular structure the¬ reof 6 in figure 1, with the relating alarms, as well as monitor 20. In this case, the advantage of an absolute indipendence is obtained in receiving notice of obstacles for each single vehicle.