|European Case Law Identifier:||ECLI:EP:BA:2009:T160806.20091020|
|Date of decision:||20 October 2009|
|Case number:||T 1608/06|
|IPC class:||H04N 5/335|
|Language of proceedings:||EN|
|Download and more information:||
|Title of application:||Imaging device and timing generator|
|Applicant name:||Axis AB|
|Relevant legal provisions:||
|Keywords:||Inventive step - (yes) after amendment|
Summary of Facts and Submissions
I. The appeal is against the decision of the examining division to refuse European patent application No. 03 713 171.1, published as WO 03/088653 A1.
II. The examining division refused the present application on the ground that the subject-matter of the claims then on file lacked an inventive step. The decision under appeal referred to the following documents:
D1: US 5 581 303 A,
D4: JP 2001 238138 A and
D5: US 2002/0135690 A1.
III. The applicant appealed and filed new claims with the statement of grounds of appeal.
IV. In a communication dated 22 April 2009 under Rule 100(2) EPC the board indicated its provisional opinion that grant of a patent could only be envisaged once minor amendments had been made to the application.
V. With a letter dated 8 May 2009, in reply to the board's communication, the appellant filed claims 1 to 8 replacing the claims filed with the statement of grounds of appeal and replacement pages 2, 2a, 2b, 2c, 3 and 6 of the description.
VI. Claim 1 reads as follows.
"A timing generator (12) for an imaging system, comprising:
an output timing signal controller (236; 318), which output timing signal controller (236; 318) is arranged to provide a plurality of output signals at a plurality of signal lines thereof (414),
an horizontal position counter and a vertical position counter (204) arranged to count clock cycles for keeping track of an x and y coordinate of a pixel presently handled,
said timing generator (12) being characterized by:
a programmable program memory (220; 316) that is arranged to comprise program instructions for controlling the generation of timing signals,
a timing generator controller (222) for processing the program instructions from the program memory (220; 316),
the timing generator controller (222) including a decoder (224; 302) for decoding program instructions from the memory (220; 316), the decoder (224; 302) being arranged to output at least one control signal (402) and a plurality of parallel signals forming a bit pattern and constituting an output timing signal specification (404), the output timing signal specification (404) determining the appearance of the output signals in response to the decoding of said instructions,
the output timing signal controller (236; 318) being connected to the timing generator controller (222) for reception of the at least one control signal (402) and the output timing signal specification (404), and
the output timing signal controller (236; 318) further comprising means for performing an XOR operation (412) and comprising at least one selector (406), said means for performing an XOR operation (412) being arranged to receive said plurality of output signals (414), to receive said output timing signal specification (404) or a bit pattern of zeros from the selector (406) depending on the at least one control signal (402), and to output signals resulting from the XOR operation between the signals (418) from the selector (406) and said plurality of output signals (414), wherein the output from the means for performing an XOR operation (412) is connected to the plurality of signal lines (414) of the output timing signal controller (236; 318)."
The amendments in claim 1 with respect to claim 1 on which the decision under appeal was based have been indicated in italics.
VII. The reasoning in the decision under appeal can be summarised as follows.
The closest prior art was D4. D5 was used as a translation of D4, as D4 was the priority document of D5.
The subject-matter of claim 1 differed from the teaching of D4 in that the timing generator was programmable like a general purpose microprocessor. Therefore the problem to be solved was how to increase the flexibility of the timing generator. This problem was formulated in D1, column 1, lines 32 to 35. Thus a person skilled in the art would have combined the teachings of D4 and D1. D1 disclosed a programmable program memory that was arranged to comprise program instructions for controlling the generation of timing signals. D1 also disclosed a timing generator controller and an output timing signal controller as specified in claim 1 then on file. Therefore a person skilled in the art would have arrived at the subject-matter of claim 1 then on file without an inventive step by combining the teachings of D4 and D1.
VIII. The appellant's arguments can be summarised as follows.
D4 was the closest prior art. The problem of increasing the flexibility of the timing generator for an imaging system was already solved in D4 by arranging a computer that stored edge data and time series data which could be downloaded to an edge data RAM and a time-series data RAM. D4 disclosed that this configuration could be used to change the timing to drive the solid state imaging device even after the timing generator was completed. A person skilled in the art would not have tried to find a solution to the above problem in D1 because D1 concerned the timing of a video display. The timing of an imaging system was much more complex than the timing of a video display.
By means of the timing generator according to claim 1 it was possible to add an instruction in the programmable program memory to provide for altering at least one of the output signals. The instruction could be programmed without the programmer knowing the present state of the other output signals and without affecting these other output signals. This was possible by means of an arrangement of a selector and a means for performing an XOR operation as specified in claim 1. That is, each output signal line connected to an XOR operation provided with, for instance, a logical "1" from the instruction was altered from its present state, whereas each output signal line connected to an XOR operation provided with, for instance, a logical "0" kept its present state.
The objective problem was to facilitate the control of individual output signals, and D4 did not recognise this objective problem. In D4 the output signals were generated as logical combinations of signals from a time-series data ROM and two edge data ROMs in a mixer. Thus, according to D4, it was necessary to obtain information from all the ROMs, of the state of the rest of the output signals and of the logical function in the mixer in order to be sure that the alteration did not alter output signals that should not be affected. D1 did not provide any teaching that led a person skilled in the art to the solution of the objective problem either. Even if a person skilled in the art tried to combine the teachings of D1 and D4, the combination failed to disclose all the features of present claim 1.
IX. The appellant requested that the decision be set aside and a patent be granted based on the new claims. The appellant also requested oral proceedings if the request was not allowed.
Reasons for the Decision
1. The appeal is admissible.
2. Allowability of the amendments (Article 123(2) EPC)
2.1 Claim 1 is based on original claim 1 and comprises additional features disclosed in the description as originally filed. Namely the horizontal and vertical position counters are disclosed in figure 2 and on page 9, lines 15 to 20, and page 10, lines 26 to 29. The features specifying the timing generator controller are disclosed in figure 3 and on page 13, lines 32 to 37, and page 15, lines 3 to 6. The features of the output timing signal specification are disclosed on page 19, lines 25 to 35, in conjunction with page 18, line 36, to page 19, line 4. The features specifying the output timing signal controller are disclosed in figures 3 and 4 and on page 20, lines 5 to 30. In particular the feature of "at least one selector" is disclosed because the mask selector (406) and the signal selector (408) in figure 4 relate to distinct functionalities which are individually disclosed.
2.2 Claims 2 to 6 are original dependent claims 2 to 6. Claims 7 and 8 are disclosed in original claims 7 and 11.
2.3 The description has been amended to acknowledge the prior art documents D1 and D4 and has been brought into conformity with the current claims.
2.4 Thus the present application documents comply with Article 123(2) EPC.
3. Inventive step (Article 56 EPC 1973)
3.1 It is undisputed that none of the available documents destroys the novelty of the timing generator according to claim 1. The board agrees. Furthermore the appellant has not challenged the use of D5 as a translation of the closest prior art D4. Hence the board, based on the presumption that the disclosure of the Japanese patent application D4, from which the post-published US patent application D5 derives its priority, is fairly reflected by D5, will refer to the disclosure of D4 in the light of D5.
3.2 D4 discloses a timing generator having the features of the precharacterising portion of claim 1. More specifically, D4 discloses in its embodiment of figure 3 a timing generator (14) for an imaging system, namely a solid state imaging device such as a CCD (see D5, paragraph ). The timing generator (14) of D4 comprises an output timing signal controller ("combinatorial logic circuit (MIX) block" 60, see D5, paragraph ) arranged to provide a plurality of output signals at a plurality of signal lines thereof (H1, H2, V1 to V4, CH1, CH2, PROC), a horizontal position counter (41) and a vertical position counter (31) being arranged to count clock cycles to keep track of an x and y coordinate of a pixel presently being handled (see D5, paragraph ).
3.3 The timing generator disclosed in D4 has some flexibility on a general level as to how the timing pulses are generated. Repetitive pulse patterns are stored as time-series data for several types of timing pulses that change in mutually correlated manners. For timing pulses that should be set on an individual basis the addresses of the leading and trailing edges thereof are stored as edge data (see D5, paragraph ). Specifically a "time-series data ROM 50 is a memory for storing data representing the logical level repetitive pattern of an output pulse train." And "edge data ROMs 33 and 43 are memories for storing data representing at what counts of the V-and H-counters 31 and 41 control pulses should change their logical levels" (see D5, paragraph ). Hence by changing the ROMs other timing signals may be produced. In other embodiments an external ROM 70 stores second, alternative time-series data and second, alternative edge data (see figure 8 and D5, paragraphs  and ). A PC 100 may be provided in addition to, or instead of, the external ROM 70 to store third edge data and third time-series data in respective RAMs as a further alternative. With PC 100 the timing pulses can be changed without redesigning the timing generator (see figure 9 and D5, paragraphs  to ).
3.4 The features specified in the characterising portion of present claim 1 (in particular the selector in combination with the XOR means controlled by the timing generator controller processing the instructions from the programmable program memory) have the technical effect of allowing a subset of output signals to be altered without considering any other output signals (see page 20, lines 27 to 30, of the application, instructions "inv_sig <mask>" and "inv_extra <mask>" in Tables 1 and 2). For instance, the output signals may represent an instruction word which is provided as data to several devices which receive timing signals from the timing generator, and certain bits are enable bits which possibly need to be manipulated individually (see page 14, line 15, to page 15, line 2). The board thus concurs with the appellant that the objective technical problem may be seen in facilitating the control of individual output signals.
3.5 D4 does not address the problem of selectively manipulating individual bits of the output signal. D1, the second document used in the decision under appeal, is not concerned with the manipulation of individual bits in the output signal either. D1 discloses a timing circuit for an object completely different from a CCD, namely for a video monitor. The timing circuit has some flexibility because it comprises an instruction SRAM.
3.6 A person skilled in the art, familiar with the teaching of D4 and faced with the problem of altering a subset of output signals individually without considering any other output signals, would not have considered combining document D1 with the teaching of D4. Firstly, D1 concerns a technical field (timing of video displays) different from that of D4 (timing of imaging devices such as CCDs, which require more complex timing signals). Secondly, the particular problem of altering a subset of output signals individually without considering any other output signals is not discussed in D1 and D1 does not disclose any solution to this problem. And thirdly, D4 essentially teaches altering the output signals by providing alternatives to the data stored on the ROMs or, possibly, by downloading from a PC a complete set of data into RAMs. But the particular solution to the problem, as specified in claim 1, is not suggested in D1 or D4. Thus a person skilled in the art would not have arrived at the subject-matter of present claim 1 by combining documents D4 and D1 in an obvious manner.
3.7 The other documents on file are not closer to the invention than documents D4 or D1.
3.8 Hence the board judges that the timing generator according to claim 1 involves an inventive step (Article 56 EPC 1973).
4. Claims 2 to 8 are dependent on claim 1. Hence their subject-matter also involves an inventive step.
5. Thus the board allows the appeal. Hence there is no need to hold oral proceedings.
For these reasons it is decided that:
1. The decision under appeal is set aside.
2. The case is remitted to the first instance with the order to grant a patent in the following version:
Pages 1, 4, 5 and 7 to 22 as published.
Pages 2, 2a, 2b, 2c, 3 and 6 filed with the letter of 8 May 2009.
No. 1 to 8 filed with the letter of 8 May 2009.
Sheets 1/3 to 3/3 as published.