1964-04-15

Abstract of GB955595 955,595. Photo-electric devices. GENERAL ELECTRIC CO. Ltd., and FERRANTI Ltd. July 11, 1961 [July 15, 1960], No. 24728/60. Heading H1K. [Also in Division G1] A semi-conductor body 1 with a PN junction is encapsulated in a transparent body 7 attached to or integral with an hemispherical lens 8. The arrangement converts solar to electrical energy. The body 1 comprises a slice out from a P-type silicon crystal with an N-type zone formed by diffusion into a major surface. Gold electrodes 2 and 3 are provided, electrode 2 being annular to provide a window through which light may fall on the junction. A brass plate 4 with a screw stem 5 provides one terminal while a soldered wire 6 provides the second terminal. The device is encapsulated in a transparent body 7 of epoxy or acrylic resin. A hemispherical lens 8, cast or machined to shape separately, is bonded to the body 7 or, since it is made of the same material as the body 7, may be cast with it in the process of encapsulation.

0

1964-04-15

H01L31/00 ; H01L31/052 ; H01L31/00 ; H01L31/052

H01L31/00 ; H01L31/052B

GB19600024728 19600715

GB19600024728 19600715

NL267026 (A); NL133022C (C)

1	Improvements in or relating to devices for converting solar energy into electric energy
	Inventor: CHANDLER THOMAS WILFRED; SERGEANT GEOFFREY	Applicant: GEN ELECTRIC CO LTD; FERRANTI LTD
	EC:H01L31/00; H01L31/052B	IPC: H01L31/00; H01L31/052;H01L31/00(+1)
	Publication info: GB955595 A - 1964-04-15
2	IMPROVEMENTS IN OR RELATING TO DEVICES FOR CONVERTING SOLAR ENERGY INTO ELECTRIC ENERGY
	Inventor: CHANDLER THOMAS WILFRED; SERGEANT GEOFFREY	Applicant: GEN ELECTRIC CO LTD
	EC:H01L31/00; H01L31/052B	IPC: H01L31/00; H01L31/052;H01L31/00(+4)
	Publication info: MY16465 A - 1965-12-31
3	Improvements in or relating to devices for converting solar energy into electric energy
	Inventor:	Applicant:
	EC:H01L31/00; H01L31/052B	IPC: H01L31/00; H01L31/052;H01L31/00(+1)
	Publication info: NL133022C C - 0000-00-00
4	Improvements in or relating to devices for converting solar energy into electric energy
	Inventor:	Applicant:
	EC:H01L31/00; H01L31/052B	IPC: H01L31/00; H01L31/052;H01L31/00(+1)
	Publication info: NL267026 A - 0000-00-00

1	A PIR sensor device.
	Inventor: GOUGH KEITH ADRIAN	Applicant: BRIDISCO LTD (GB)
	EC:G08B13/191	IPC: G08B13/191;G08B13/189; (IPC1-7): G01N21/84
	Publication info: GB2269011 - 1994-01-26

WHAT WE CLAIM IS: -

1 A device for converting solar energy into electrical energy comprising a semiconductor body having a substantially planar p-n junction and a lens which is arranged to concentrate on to the p-n junction light which is incident in at least one plane that is normal to the plane of the junction and which has substantially all angles of incidence between 0 and 180 c to the plane of the junction so that the device gives a greater output of electrical energy than would be obtained without the lens, the lens being mounted so that there is no air gap between the lens and the p-n junction.

2 A device according to Claim 1 wherein, at least in said plane that is normal to the plane of the junction, the aperture of the lens is larger than the dimension of the active area of the junction.

3 A device according to Claim 1 or Claim 2 wherein the semi-conductor body is of silicon.

4 A device according to Claim 1, Claim 2 or Claim 3, wherein the lens is hemispherical.

A device according to any preceding claim wherein a semi-conductor body is encapsulated in a synthetic resin and the lens is formed of the said resin.

6 A device according to Claim 5 wherein the lens is bonded to the encapsulated body.

7 A device according to Claim 5 wherein the lens is integral with the encapsulating resin, the lens having been formed at the time of encapsulation.

8 A device for converting solar energy into electrical energy substantially as hereinbefore described with reference to the accompanying drawing.

For the Applicants, J D DOLWIN, Chartered Patent Agent.

Leamingtou Spa: Printed for Her Majesty's Stationery Office, by the Courier Press (Leamington) Ltd -1964 Published by The Patent Office, 25 Southampton Buildings, London, W C 2, from which copies may be obtained.

955,595

PATENT SPECIFICATION

DRAWINGS ATTACHED 95 C:__ f gmwb Inventors: THOMAS WILFRED CHANDLER < // k 4/i:>, and GEOFFREY SERGEANT Date of fifling Complete Specification: July It, 1961.

Application Date:July 15, 1960 No 24728160 Complete Specification Published: April 15, 1964.

Crown Copyright 1964.

Index at acceptance:-1 11 K( 1 D 3 B, 2520, 4 F 9, 4 F 11, 4 F 27, 5, 7 A 1); G 1 A 5 M 1 International Classification:-H 01 e, 1 (G 01 j) COMPLETE SPECIFICATION

Improvements in or relating to Devices for Converting Solar Energy into Electric Energy We, THE GENERAL ELECTRIC COMPANY LIMITED, formerly of Magnet House, Kingsway, London, W C 2, and now of 1, Stanhope Gate, London, W 1, and FERRANTI LIMITED, of Hollinwood, Lancashire, both British Companies, do hereby declare the invention, for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: -

This invention relates to devices for converting solar energy into electric energy.

It has previously been proposed to use a silicon body having a p-n junction for the purpose of deriving electric energy from solar energy, the electric energy so obtained being utilised, after passing through a unilaterally conducting device, to charge a secondary battery If such a body is fixed relative to the ground, there is, of course, a change in the angular relationship between the sun and the silicon body as the sun travels across the sky during the day For optimum electrical output throughout the day, the body is normally mounted in such a position that there is maximum output around mid-day It is then found, however, that the conversion efficiency from solar to electric energy falls off in the early morning and in the evening so that there is appreciably less output even though it is still quite light One object of the present invention is to reduce this falling off in efficiency.

Another object of the present invention is to increase the amount of electrical energy that can be obtained from a silicon or other semiconductor body of given size.

According to the present invention, a device for converting solar energy into electrical energy comprises a semiconductor body having a substantially planar p-n junction and a lens which is arranged to concentrate on to the p-n junction light which is incident in at least one plane that is normal to the plane of the junclPrice tion and which has substantially all angles of incidence between O and 1800 to the plane of the junction so that the device gives a greater output of electrical energy than would be obtained without the lens, the lens being mounted so that there is no air gap between the lens and the p-n junction.

Preferably the semiconductor body is of silicon and the lens is hemispherical If the body is encapsulated in a synthetic resin, the lens may conveniently also be formed of the said resin, the lens either being bonded to the encapsulated body or being formed at the time of encapsulation.

One construction of a device in accordance with the present invention for converting solar energy into electrical energy will now be described with reference to the accompanying drawing which shows diagrammatically a cross-section through the device.

Referring to the drawing, the device comprises a thin disc 1 of p-type silicon which is, in fact, a slice cut from a single crystal and which has suitable material diffused in known manner into one of its major surfaces during manufacture to form a thin n-type zone Gold electrodes 2 and 3 are formed on the two major surfaces of the disc, the electrode 2 on the previously mentioned surface being in the form of an annular band leaving a circular window through which, during operation of the complete device, light may fall on the junction between the p-type and n-type silicon.

The electrode 3 on the back surface of the disc 1 is circular and completely covers that surface.

A circular brass plate 4 is secured, by welding or soldering, to the electrode 3 on the back of the silicon disc 1 This plate 4 has a screwthreaded portion 5 extending from that side of the plate which is remote from the silicon disc 1 and this portion constitutes one terminal of the device One end of a wire 6 is soldered 59595 to the annular electrode 2 and this wire constitutes the other terminal of the device.

The silicon disc 1 and the brass plate 4 are encapsulated in known manner in a mass 7 of thermo-setting synthetic resin, for example an epoxy resin or an acrylic resin It is, of course, essential for this resin to be transparent so that light may fall on the p-n junction of the disc 1 The two terminals 5 and 6 of the device project through the encapsulating material.

During manufacture of the device, the plane surface of a hemispherical lens 8 is bonded, for example by glueing, to the encapsulated disc 1, the lens 8 having been previously shaped either by casting or by machining from solid material The material of the lens is the same resin as that used for encapsulation There is thus no air gap between the encapsulated disc 1 and the lens 8 which rnight, if present, cause light falling on the lens from some directions to be internally reflected instead of being directed on to the p-n junction.

In a preferred form of the device described above, the said window, which defines the active area of the p-n junction, has a radius of 7/16 inch while the hemispherical lens has a radius of 19/32 inch.

It will be appreciated that the lens 8 serves to increase the effective area of the device on which useful light may fall Thus the ray 9, which in the absence of the lens 8 would fall on the electrode 2, falls on the active area of the p-n junction defined by the circular window in the electrode 2.

Furthermore the provision of the lens 8 appreciably increases the period, assuming continuous sunshine, over which the device may be used to give a useful electric output This may be seen by considering light falling on the device in the direction of the arrow 10.

Without the lens 8 the active area of the p-n junction as seen in the direction of the arrow only has the dimension L 1 The lens 8 increases this effective dimension to Lo.

It will, of course, be appreciated that the lens 8 need not be formed separately and then bonded to the encapsulated silicon disc but may be formed by casting at the time of encapsulation.