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Publication numberUS2976105 A
Publication typeGrant
Publication dateMar 21, 1961
Filing dateFeb 6, 1956
Priority dateDec 11, 1954
Also published asDE1040110B
Publication numberUS 2976105 A, US 2976105A, US-A-2976105, US2976105 A, US2976105A
InventorsHarry Sparke, Leslie Rose
Original AssigneeKirklees Ltd
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Means for generating and controlling random effects
US 2976105 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

March 21, 1961 1.. ROSE ET AL MEANS FOR GENERATING AND CONTROLLING RANDOM EFFECTS Filed Feb. 6, 1956 5 Sheets-Sheet 1 March 21, 1961 1.. ROSE ET AL MEANS FOR GENERATING AND CONTROLLING RANDOM EFFECTS Filed Feb. 6, 1956 5 Sheets-Sheet 2 March 21, 1961 L. ROSE ET AL 2,976,105


\ \nnuuuuununuu/Inuuun) (J u\n u FIG] March 21, 1961 ROSE ET AL 2,976,105

MEANS FOR GENERATING AND CONTROLLING RANDOM EFFECTS Filed Feb. 6, 1956 5 Sheets-Sheet 5 MEANS FOR GENERATING AND CONTROLLING RANDOM EFFECTS Leslie 'Rose, Whitefield, and Harry Sparlre, Holcombe Brook, England, assignors to Kirklees Limited, Bury, England, a company of Great Britain Filed Feb. 6, 1956, Ser. No. 563,806

11 Claims. (Cl. 346-33) This invention relates to means for generating randomly occurring impulses or signals which can be employed to operate or control apparatus where randomly occurring effects are desired.

The said means according to the invention comprise a pin-table having a large number of ranks and files of pins, into the top of which are fed at constant and predetermined time. intervals a succession of steel balls, the balls falling by gravity through the pin-table, being randomised as to time of descent thereby, each ball being delivered on to a device which while a ball is in contact therewith will cause the generation of an impulse or signal which can be employed either directly or through a relay to control the apparatus for producing the desired randomly occurring effects. I

In one form of the invention each ball is delivered onto a pair of teiminals such as electrified rails thereby causing the closing of an electric circuit and the passage of a small current which actuates a relay, the relay in turn operating a magnetically operated clutch controlling the apparatus.

The characteristics of a pin-table are such as to make it particularly suitable for the purposes mentioned. The time taken for the descent of the balls from the .point of entry to the beginning of the device at the bottom of the table is random, but conforming to the mathematical laws of the so-called Gaussian distribution, or normal distribution. Such distributions are characterised by measurement ,of the mean time of .descent and the standard deviation thereof.

The standard deviation is a. measure of the extent of.

randomness and is a fixed property of the particular pin-table, the particular ball and the manner of its use. The standard deviation can be adjusted to suit particular purposes over wide range, as for example by using another -b a1l :size, altering the angle of inclination of the:

pin-table, modifying the number of rows of pins, ,or making the exit end of the maze non-rectangular. The form of pih table having the ,exit end at right angles to the straight line of descent has the least standard deviation compared with designs having sections removed from the bottom edge or designs having extra rows put in to produce a triang lar exit.

' The time of descent of the balls is of on consequence in the invention. Nevertheless, the measurement of such timesgfor 100,0 successive descents for example, is the basis o e e tion of th rroper desi of Pin-table for the allotted task, in order to determine the standard deviation of the table. From the point of view of theprediction-of the standard deviation of slubbing impulses, the important criterion is the standard deviation of successive differences.

This is not :thesame as the standard deviation of the pin table, but is related to it by the square root of 2.

Standard jDeviatlo n of Standard Deviation intervals between 2X of time of descent successive balls oi the pin table th s ba i a rai -tab e destgnc n b s e ted t give he des red r nd ss,-

The mathematics of the Gaussian theory enable one to Patented Mar. 21, 1961 ICC predict what percentage of impulse intervals will lie in any given range. For instance, if the standard deviation of successive differences is exactly half the fixed time between the entry of successive balls into the table, then 2.28% of all slubs will be at intervals of more than twice the average, and 2.28% of all slubbing impulses will coincide, or appear as reversed order of ball impulses. The use of the Gaussian probability tables from wellknown books of statistics makes it easy both to select the desired standard deviation for a given efiect and to predict the effect of any given standard deviation.

It is found for many purposes to be satisfactory to use a standard deviation about half the fixed time of entry (a coefficient of variation of 0.5) although the invention is by no means limited to the use of this value.

The characteristics of this invention which make it so valuable are:

(i) The device gives random periods with no repeat whatsoever, and

(ii) The fact that each ball, though random in its time of descent, controls the time interval between it and the ball before, and in its turn controls partially the next time interval. Any ball which happens by change to get through the maze quickly tends to produce a short interval slub, but also tends to arrange that the next interval will be a long one. The average therefore, tends to stay constant, and is in fact controlled by the fixed rate of entry of balls into the maze of the table.

-When balls leave the exit of the maze they do so with varying velocities. The distribution of exit velocities is also Gaussian. As a result of this, the length of time spent upon the electrified rails is random and Gaussian, with the result that not only are the periods random in a fully satisfactory manner, but the length of the actual period is randomly con-trolled. This feature also can be adjusted to desired levels in practice by selection of a proper length to the electrified rails, or other device and also the inclination thereof to the horizontal.

One application of the invention is the production of slub yarns, i.e. yarns having thin and thick places and in the production of such yarns the positions in which slubs appear along the thread should be regulated in certain ways if the fabric made from such thread is to have a desirable appearance. The two main conditions which the distribution of the slubs should satisfy are as follows:

(1) The interval distribution should be random so as to avoid unsightly patterns in woven fabric made from the yarn. v I I (2) Notwithstanding Condition 1, the number of slubs in a given moderate length of yarn, for example a length of yarn expected to contain 25 slubs, should remain approximately constant, so as to avoid the appearance of either relatively bare or relatively crowded regions in the fabric, i.e. patchiness.

The requirement that the fabric shall be free from patchiness can be expressed as a statement that a slub should always appear near to its expected position. For example, suppose a slub yarn is to be made having an average over very long lengths of 1 slub per metre, but that individual slubs are to be permitted to have intervals of from 10 cms. to 200 cms. If the arrival of each slub is an independent random event, then quite easily by chance there could be, say, 10 slubs in succession, all of them less than 50 cms. apart. The result of this would be a crowded portion of fabric, and in the case of the tenth interval of say 50 cms. the last slub would appear at 500 cms. whereas the expected position, based on ideal control of slub density, would be 1000 cms. from the start.

These conditions lead to the postulation that the ideal control of slub formation isone of which is random but in which the chance arrival of a short-period slub carries with it the probability that the next slub is a randomlyselected long-period slub, so as to tend to maintain the average constant. 7 g

Another application of the invention is for the generation and control of effects such as the printing of randomly spaced designs upon woven fabric.

In the printing of fabrics, the desired design may be imprinted either discontinuously upon lengths of fabric, as in the block printing method, or continuously as in the case of rotary printing cylinder methods. In either case, whatever the chosen design may be, it will repeatitself along a length of fabric in, sections corresponding either to the length of the block, or to the circumferential length of the cylinder. 1

Novel and particularly interesting printed effects are obtained if, instead of with repetitive designs, the-fabric 'is'- imprinted with completely random effects. If the'eye is intended not to see a pattern underlying such broken effects, it is important not only to randomise the printing of each device, but to do so extremely effectively, because the eye is able to discern repetition if it exists. Moreover, it has been found that complete randomisation is not entirely satisfactory if it entails, by chance alone, the production of areas of the fabric having a mean density of imprint greatly different from that of the fabric as a whole.

In such application a novel effect of random printing is produced by means of a small printing roller which tra-. verses a length of cloth, whilst the cloth is progressed along its length at a uniform or non-uniform speed. During most of the traversing passage of the cloth the print-' ing roller, equipped with means of delivering pigment suspensions of known types, does not make contact with the cloth. The printing roller is also'equipped, however, with a solenoid-operated dipping mechanism, which when ener-- gised causes the printing roller to make firm contact with the cloth, and imprint a design, such as a linear streak,- thereon. The energising of the dipping mechanism may be controlled by means of a pin-table-relay mechanism described in this application. By this means, a non-re-- peating pattern of impregnated design is obtained upon the fabric.

The random control of events or processes including the formation of slub yarn or novel printing effects can be obtained by the use of a pin-table in a different way.

According to .this part of the invention, the pin-tabl-is" not used as such for the control of the operation itself, but for thepreparation of electro-mechanicalrecords, or copies of the performance of the pin-table. The copies or records are then used for control ofthe operation itself, with certain practical advantages which will now be described.

The pin-table itself produces a series of electrical impulses, having a mean spacing corresponding to the rate of entry of the balls into the pin-maze (with a small allowance if any significant fraction of the balls arrives in inverted order, or simultaneously), and a spread of individual intervals according to the construction of the pin-maze and its resulting coefficient of variation. If it is desired to control a second process having a different mean rate of events, but the same coefiicient of variation, a second pin-table must be employed. If, however, a record-ing is made of the performance of a pin-table suitable for oneoperation, the recording can in future replace the pin-table in actual control, and an additional record ing, run through at a faster or slower rate, will control processes needing different average rates of event but the same coefficient of variation, without the need to construct and adjust further pin-tables.

One method of producing a suitable recording of the behavior of a pin table is the following:

The recording is a length of 35- mm. photographic film, and the apparatus used to imprint the record upon the film consists of a traversing point source of light focussed upon the film. The film is advanced by slowly rotating sprockets engaging in the usual perforations, and the rate of traverse, at substantially uniform to and fro speed is adjusted so that the point source makes a closely packed zig-zag upon the film surface. With care to achieve a point source not substantially greater than 0.635 mm. in diameter, it is possible to arrange the relative speeds of traverse of light source and the forward movement of film so that each zig-zag is approximately 3.2 mm. What-' ever is chosen, the ratio of relative speeds used is maintained constant, not only throughout the recording, but.

also in playing back. It is a convenience if each zigzag occupies a length of film equal to the film perforation distance. I g

The electrical impulses from a suitable pin-table device are used to illuminate the point source of light intermittently. Since the time during which the impulse lasts is finite, there is produced upon the film an elongated latent image in the form of a. streak, visible on photographic development, for each electrical impulse.

of it, i.e. the duration.

The developed film forms a master-negative" from which film prints are made to become the actual con-' trollers. The prints consist of transparent streaks upon a black background.

In use as a controller, the recording is played back in an apparatus consisting of a small collimated source oflight on the top surface of the film and a photo-electric 1 cell on the other side. These two are traversed together, using the same traverse linear speed ratio as used in the recording, back along the path made in the originalrecording. Each transparent streak produces an electrical the system in question-slub yarn production, for ex ample.

It is possible using this system to obtain an electro- 'mechanical record of up to 100,000 events, a number lengths of time, 24 hours for example, it is possible to make the reversal period to coincide with a discontinuity.

which can certainly be regarded as non-repeating for practical purposes. When the recording comes to its end, it

may be reversed and the whole path retraversed. This,

however, gives rise to a temporary inverted repeatf pattern at or near to the point of reversal. In most cases this is not objectionable, but where it is so, the operation of the machine can be interrupted whilst the film is backwound, or alternatively if this procedure is too timewasting, a second copy, already backwound can be in-- serted. Since the recording can be made to last for long in the production process. In this case, if the film is allowed to start its reversed path several minutes before; the controller is switched on, inverted repeat patterns disappear for practical purposes.

In order that the invention may be fully understood reference will now be made to'the accompanying drawings, in which:

Fig. 1 is a diagrammatic isometric view of a pin table device for carrying out the invention,

Fig. 2 is a diagrammatic view showing the impulses.

derived from the pin table applied to the production of continuous filament viscose rayon,

. Figs. 3 and 4 are a diagrammatic side view and plan respectively showing the impulses derived from the pinphotograph film rectable applied to the production of a 0rd of the impulses,

Figs. 5 and 6 are a diagrammatic side view and plan respectively showing the impulses recorded and film being;

zontal rows of pins 7, the pins in one row being staggered, inrelation to those in adjacent rows. Theentry tothc' The position: of the streak defines the impulses spacing, and the length pin table is in the form of a vertical slot to which the balls are fed singly from a rotating wheel 2 to which they are fed-from a ball storage drum 1. The wheel 2 is provided with compartments 3 each of which receives a ballfrom the drum 1 as the wheel rotates and delivers it to the entry 5. A ball 4 is seen just leaving one of the compartments 3 in the wheel 2. Thus each time the wheel 2 rotates as many balls are delivered to the pin table as there are compartments 3 in the wheel.

The pin table 6 is inclined at a suitable angle say 45 and at the bottom the sides are inclined to one another to direct the balls to an outlet hole 8 through which they fall onto a pair of live rails 10 which are inclined to the horizontal. at 11 through the wires 14 to a terminal block 12 which in turn is connected by the wires, 15 to a relay 13, the output wires of which are shown at 16.

The rails 9 are inclined to the horizontal so that when a ball falls thereon it bridges the rails and completes the electric circuit to the relay 13. As the rails 10 are inclined the balls will roll down the rails and the circuit to the relay will be maintained until the ball rolls olI the rail. The portion 9 of the rails 10 onto which the balls fall from the hole 8 are preferably of insulating material and direct the balls on to the live position 10. The halls roll from the'live rails 10 'to a chute 17 which delivers them to a. hopper '18 from which they are fed to an endless chain'conveyor 19 which carries them up to a chute 20 at the top of the ball storage drum 1.

Fig. 2 shows the control from the relay 13 to the pumps supplying the jets producing continuous filament viscose rayon. In this figure, the impulses are transmitted to the relay 13 by the balls 4 bridging the live rails 10 as previously described with reference to Fig. 1.

The relay 13 controls through the connections 16 a clutch member 36 of an electro-magnetic clutch 34, one member of which is mounted on a shaft 40 driven from a motor 41 and carrying a fiy wheel and the other member drives a shaft 31 through a reduction gear 33 anda worm and worm wheel gear 32.

,Each jet is connected respectively by the viscose supply line 22 to a constant volume pump 23 fed from a continuous viscose supply 21 and through the supply line 29 to an intermittent pump 28' driven from the shaft 31 and supplies viscose from an auxiliary supply 27. Thus the jets 25 are supplied continuously with a constant volume of viscose by the pump 23 and supplied intermittently by the pump 28 with an auxiliary volume volume of viscose, the supply of this auxiliary volume being controlled through the clutch 34 and gearing 33 and 32 according as to whether the clutch members are closed or 'not by the relay 13.

When an auxiliary supply of viscose is supplied to the jet 25, a slub or thick place is formed in the yarn and the occurrence of the slubs coincides with the occurrence of a ball on the live rails 4.

In the case of cotton or other yarns which are drafted by passing between pairs of drawing rollers slubs or thick places in the yarn can be produced by altering the relative speeds of the drawing rollers, and in this case the relay 13 is employed to actuate gearing which will vary the relative speed of the rollers.

Referring to Figs. 3 and 4 the relay 13 controls a lamp 62 in a projector 63 which projects through a small aperture 64 onto a film 65 passing through a gate 66. The film 65 is drawn through the gate 66, in which it is exposed, by the sprocket wheel 67. Thus each time the lamp 62 is illuminated a spot of light will be projected onto the film 65 through the aperture 64.

To shorten the length of the film 64 necessary the projector 63 is given a reciprocating up and down movement such that if the lamp 62 were continuously illuminated a continuous Zig-zag line, such as the broken line 68, shown in the view of the film in Fig. 7. Owing to the light from the lamp 62 being intermittent however The connection rails 10 are connected a series of dot like images 69 located on the broken line 68, are formed at random thereon. The desired reciprocating movement of the projector 63 is obtained from the cam 70 which engages a cam follower 71 .slidably mounted in a guide 72 and secured to the projector 63. The cam 70 is driven through the worm and worm wheel gearing 73 from the driving shaft 74 from which the sprocket wheel 67 and the film take up spool 75 also derive their motion through gearing.

A positive film is made from the negative film produced as described in the preceding paragraphs on which positive film the random dot like images 68 are transparent, the remainder of the film being opaque. Apparatus for using this positive film for obtaining random efiects is illustrated in Figs. 5 and 6. The positive film again designated 65 is passed through a gate 54 of a projector 76 containing a continuously illuminated lamp 42 the light from the lamp being projected onto the film 65 through a small aperture 58.

At the other side of the film 65 to the gate 54 a photoelectric cell 43 is arranged so that each time light from the projector 76 passes through a transparent dot-like image on the film the photo-electric cell 43 is actuated and operates an amplifier 60 through the electric connections 59. The amplifier 60 is connected by the connections 61 to a relay 13 corresponding with the relay 13 of Figs. 1 and 2 and which is connected by the connection 16 to the control of the apparatus or machine to give.

the desired random operation thereto.

As in the film producing device shown in Figs. 3 and 4 the projector 76 of the device of Figs. 6 and 5 is reciprocated vertically by the cam 46 driven through the worm and worm wheel gearing 47 from a driving shaft 48, the cam reciprocating the projector through the cam follower 45. The photo-electric cell 43 is also reciprocated vertically in unison with the projector 76 by a second cam 46 driven from the driving shaft 48 through the worm and worm wheel gearing 47 The sprocket 55 which draws the film through the gate 54 and the film take up spool 51 are also driven through suitable gearing from the driving shaft 48.

We claim:

1. Means for generating randomly occurring impulses which can be employed to operate or control apparatus where randomly occurring effects are desired comprising a pin table having a large number of transversely staggered ranks and files of pins forming transverse and longitudinal rows which are at least several in number, means including a central inlet for feeding a succession of balls to the table at one end at constant and predetermined time intervals and causing the balls to travel through the ranks and files of pins, and means at the other end of the pin table defining a single outlet from said table through which each ball is directed after passing.

through the ranks and files of pins, and means at said outlet adapted to be contacted by each ball as it is delivered therefrom and which while a ball is in contact therewith will cause generation of an impulse which can be employed to control the apparatus for producing the desired randomly occurring effects.

2. Means for generating random-1y occurring impulses which can be employed to operate or control apparatus where randomly occurring eifects are desired comprising an inc-lined pin table having a large number of ranks and files of pins forming transverse and longitudinal rows which are at least several in number, means for feeding a succession of electrically conductive balls to the top of the table at constant and predetermined time intervals, means at the bottom of the table defining a single outlet from said table through which all of said balls are directed after passing through the ranks and files of pins, a pair of inclined rails spaced apart at the bottom of the pin table at said outlet to receive each ball as it is delivered therefrom and an electrical control circuit containing the rails and apparatus control switching means,

. 7 whereby when a ball bridges the rails an impulse will pass to the switching means and control the apparatus.

3. In apparatus for generating randomly occurring control impulses, an inclined table having a plurality of pins arranged in a bank of staggered rows which are several in number, means for introducing a succession of electrically conductive balls to said table at equal time intervals at the upper end thereof so that said balls roll down the table randomly passing throughthe pin bank, means at the lower end of the table defining a single outlet through which all of said balls. are directed after passing through the pin bank, a switch at the lower end of said table adapted to be closed by each ball after passage metal and said switch comprising a pair of inclined rails having insulated sections adapted to initially receive said balls from the table, and metal sections adapted to be bridged by the balls to close the switch for certain intervals.

6. In the apparatus defined in claim 3, means for receiving the balls after they close said switch and automatically returning them to a supply station at the upper end of the table, said ball introducing means being operably connected to said station so that the latter serves as a source of balls therefor.

7. In combination with the apparatus defined in claim 3, means connected to the output of said circuit for recording the impulses corresponding to switch actuation.

8. In combination with the apparatus defined in claim 3, means connected to the output of said circuit for utilizing said impulses to control machine operation.

9. The apparatus as defined in claim 4 wherein said 8 table has a smooth flat exposed surface between said pin bank and said inlet, said inlet being disposed so that said balls are all discharged onto said table surface be' tween said pin bank and said outlet in the same direction.

10. In combination with the apparatus defined in claim 3, a relay in said electrical circuit energizable by the randomly occurring impulses produced in said circuit, a

clutch controlled by said relay and a printing mechanism driven by said clutch whereby said printing mechanism of passage of the balls through said outlet will be pro:

duced on said film.

References Cited in the file of this patent UNITED STATES PATENTS 1,115,668 Harrington Nov. 3, 1914 1,303,099 Michaelson May 6, ,1919

1,525,144 Murphy Feb. 3, 1925 1,620,638 Faller et al. Mar. 15, 1927 1,645,122 Wallace Oct. 11, 1927 1,996,796 Dreyfus et al. Apr. 9, 1935 2,091,612 Picard Aug. 31, 1937 2,485,721 Engstrom Oct. 25, 1949 2,514,029 Connell July 4, 1950 2,555,777 Benker June 5, 1951 2,614,840 Monkres Oct. 21, 1952 2,721,782 Vilbig Oct. 25, 1955 2,736,630 Cooper Feb. 28, 1956 2,787,221 Breazeale et al. Apr. 2, 1957 2,836,850 Lindemann June 3, 51958 FOREIGN PATENTS 703,697 Great Britain Feb. 10, 1954

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Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US3091909 *May 31, 1962Jun 4, 1963Stevens & Co Inc J PIntermittent control apparatus
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U.S. Classification346/33.00R, 57/317, 57/91, 264/167, 307/141, 200/61.1, 417/420, 417/426, 346/25, 19/238, 346/107.1, 200/52.00R
International ClassificationH01J3/00, G06F1/02, H04L9/22, D01D5/00, G07C15/00, H01J3/02, H01J23/02, G06F1/03, D01H5/00, H03K3/00, H01J23/087, H01J23/08, H03K3/84, D01D5/20, H04L9/18, D01H5/36
Cooperative ClassificationD01D5/20, D01H5/36, H01J23/087, H03K3/84, G06F1/0314, H04L9/22, H01J23/08, G06F2101/14, G07C15/00, H01J3/029
European ClassificationG07C15/00, D01D5/20, D01H5/36, H03K3/84, G06F1/03P, H04L9/22, H01J3/02T, H01J23/08, H01J23/087