“In general, an eye relief of an eyepiece lens ... is about 80% of a focal length of the lens system. Therefore, a sufficient eye relief cannot be obtained in a lens system having a small focal length, which causes shading in a peripheral area of a field of view when the user is wearing glasses. To avoid this, a structure has been used in which a negative lens group and a positive lens group are arranged at the object side and the eye side, respectively, of an intermediate image of an objective lens. In this structure, a large eye relief can be ensured by arranging the negative lens group at the object side. In addition, since the Petzval sum can be reduced by using a negative lens having a large power, a field curvature aberration can be appropriately corrected. … Accordingly, an object of the present invention is to provide an eyepiece lens which includes only 5 lenses, which appropriately corrects aberrations over the entire area of a sufficiently large field of view, and which has an eye relief that is larger than or equal to the focal length of the entire eyepiece lens system”
“Field curvature is therefore not seen as an issue when designing or marketing riflescopes, which is the reason why there is little publicly available information or discussion on it nowadays or in the past before the priority date …”
“I think it is obvious to include a negative lens in the position shown in Figure 3 of the Patent to improve field curvature, and therefore useful field of view. It is obvious to do so in light of the common general knowledge and the cited prior art. In particular, it was well known that locating a negative lens between the zoom relay system and the second intermediate image plane would improve image quality (by reducing the field curvature effects of the preponderance of positive lenses) and thereby increase the useful apparent field of view”
“182 The task for the court is to determine what the person skilled in the art would have understood the patentee to have been using the language of the claim to mean. The principles were summarised by Jacob LJ in Mayne Pharma v Pharmacia Italia[2005] EWCA Civ 137 and refined by Pumfrey J in Halliburton v Smith International[2005] EWHC 1623 (Pat) following their general approval by the House of Lords in Kirin-Amgen v Hoechst Marion Roussel[2005] RPC 9 . An abbreviated version of them is as follows: (i) The first overarching principle is that contained in Article 69 of the European Patent Convention; (ii) Article 69 says that the extent of protection is determined by the claims. It goes on to say that the description and drawings shall be used to interpret the claims. In short the claims are to be construed in context. (iii) It follows that the claims are to be construed purposively – the inventor’s purpose being ascertained from the description and drawings. (iv) It further follows that the claims must not be construed as if they stood alone – the drawings and description only being used to resolve any ambiguity. Purpose is vital to the construction of claims. (v) When ascertaining the inventor's purpose, it must be remembered that he may have several purposes depending on the level of generality of his invention. Typically, for instance, an inventor may have one, generally more than one, specific embodiment as well as a generalised concept. But there is no presumption that the patentee necessarily intended the widest possible meaning consistent with his purpose be given to the words that he used: purpose and meaning are different. (vi) Thus purpose is not the be-all and end-all. One is still at the end of the day concerned with the meaning of the language used. Hence the other extreme of the Protocol – a mere guideline – is also ruled out by Article 69 itself. It is the terms of the claims which delineate the patentee’s territory. (vii) It follows that if the patentee has included what is obviously a deliberate limitation in his claims, it must have a meaning. One cannot disregard obviously intentional elements. (vii) It also follows that where a patentee has used a word or phrase which, acontextually, might have a particular meaning (narrow or wide) it does not necessarily have that meaning in context. (vii) It further follows that there is no general ‘doctrine of equivalents’. (viii) On the other hand purposive construction can lead to the conclusion that a technically trivial or minor difference between an element of a claim and the corresponding element of the alleged infringement nonetheless falls within the meaning of the element when read purposively. This is not because there is a doctrine of equivalents: it is because that is the fair way to read the claim in context. (ix) Finally purposive construction leads one to eschew the kind of meticulous verbal analysis which lawyers are too often tempted by their training to indulge”
“The European patent application or European patent may not be amended in such a way that it contains subject-matter which extends beyond the content of the application as filed.”
“The decision as to whether there was an extension of disclosure must be made on a comparison of the two documents read through the eyes of a skilled addressee. The task of the Court is threefold: (a) To ascertain through the eyes of the skilled addressee what is disclosed, both explicitly and implicitly in the application. (b) To do the same in respect of the patent as granted. (c) To compare the two disclosures and decide whether any subject matter relevant to the invention has been added whether by deletion or addition. The comparison is strict in the sense that subject matter will be added unless such matter is clearly and unambiguously disclosed in the application either explicitly or implicitly.” [97] A number of points emerge from this formulation which have a particular bearing on the present case and merit a little elaboration. First, it requires the court to construe both the original application and specification to determine what they disclose. For this purpose the claims form part of the disclosure (s.130(3) of the Act), though clearly not everything which falls within the scope of the claims is necessarily disclosed. [98] Second, it is the court which must carry out the exercise and it must do so through the eyes of the skilled addressee. Such a person will approach the documents with the benefit of the common general knowledge. [99] Third, the two disclosures must be compared to see whether any subject matter relevant to the invention has been added. This comparison is a strict one. Subject matter will be added unless it is clearly and unambiguously disclosed in the application as filed. … [102] Sixth, it is important to avoid hindsight. Care must be taken to consider the disclosure of the application through the eyes of a skilled person who has not seen the amended specification and consequently does not know what he is looking for. This is particularly important were the subject matter is said to be implicitly disclosed in the original specification”
“It has never been easy to differentiate between common general knowledge and that which is known by some. It has become particularly difficult with the modern ability to circulate and retrieve information. Employees of some companies, with the use of libraries and patent departments, will become aware of information soon after it is published in a whole variety of documents; whereas others, without such advantages, may never do so until that information is accepted generally and put into practice. The notional skilled addressee is the ordinary man who may not have the advantages that some employees of large companies may have. The information in a patent specification is addressed to such a man and must contain sufficient details for him to understand and apply the invention. It will only lack an inventive step if it is obvious to such a man. It follows that evidence that a fact is known or even well-known to a witness does not establish that that fact forms part of the common general knowledge. Neither does it follow that it will form part of the common general knowledge if it is recorded in a document. As stated by the Court of Appeal in General Tire & Rubber Co. v. Firestone Tyre & Rubber Co. Ltd. [1972] R.P.C. 457, at page 482, line 33: ‘The two classes of documents which call for consideration in relation to common general knowledge in the instant case were individual patent specifications and grave; widely read publications'. As to the former, it is clear that individual patent specifications and their contents do not normally form part of the relevant common general knowledge, though there may be specifications which are so well known amongst those versed in the art that upon evidence of that state of affairs they form part of such knowledge, and also there may occasionally be particular industries (such as that of colour photography) in which the evidence may show that all specifications form part of the relevant knowledge. As regards scientific papers generally, it was said by Luxmoore, J. in British Acoustic Films (53 R.P.C. 221 at 250): “In my judgment it is not sufficient to prove common general knowledge that a particular disclosure is made in an article, or series of articles, in a scientific journal, no matter how wide the circulation of that journal may be, in the absence of any evidence that the disclosure is accepted generally by those who are engaged in the art to which the disclosure relates. A piece of particular knowledge as disclosed in a scientific paper does not become common general knowledge merely because it is widely read, and still less because it is widely circulated. Such a piece of knowledge only becomes general knowledge when it is generally known and accepted without question by the bulk of those who are engaged in the particular art; in other words, when it becomes part of their common stock of knowledge relating to the art.”
“It is certainly difficult to appreciate how the use of something which has in fact never been used in a particular art can ever be held to be common general knowledge in the art.”
“Of course material readily and widely to hand can be and may be part of the common general knowledge of the skilled person – stuff he is taken to know in his head and which he will bring to bear on reading or learning of a particular piece of prior art. But there will be other material readily to hand which he will not carry in his head but which he will know he can find if he needs to do so (my emphasis). The whole passage is about material which the skilled man would refer to ‘as a matter of course.’ It by no means follows that the material should be taken to be known to the skilled man if he has no particular reason for referring to it.” 111 He went on to quote what Kitchin J had said at first instance in the passage I have cited and observed at [27]: “I agree with that although I personally do not find the point of principle ‘subtle’. It would be wholly subversive of patents and quite unfair to inventors if one could simply say ‘piece of information A is in the standard literature, so is B (albeit in a different place or context), so an invention consisting of putting A and B together cannot be inventive.’ The skilled man reads each specific piece of prior art with his common general knowledge. If that makes the invention obvious, then it does. But he does not read a specific citation with another specific citation in mind, unless the first causes him to do so or both are part of the matter taken to be in his head.”
“Can the skilled person readily perform the invention over the whole area claimed without undue burden and without needing inventive skill?”
“Mr Hicks has to show why something that was self-evident to all, was done by none”
“Dr Blandford therefore accepted that if a skilled person would not automatically appreciate the advantages (and disadvantages) of a lens in position C in a zoom relay system, Mai would have provided that information”